Sources behind Vitals

Last updated 18 October 2026

The published research and official references behind Vitals' targets, estimates and explanations, each listed once, grouped by topic, with where it is used in the app. Where no good source exists, the app says less rather than guessing. In the app, the same list is in Me, Settings, Sources.

Nutrition targets

• Mifflin MD, St Jeor ST et al. (1990). A new predictive equation for resting energy expenditure in healthy individuals. American Journal of Clinical Nutrition 51(2):241-247.
  Used in: Resting burn and daily calories in your plan
• FAO, WHO and UNU (2004). Human energy requirements. Report of a Joint FAO/WHO/UNU Expert Consultation. Food and Nutrition Technical Report Series 1.
  Used in: Activity level in your plan
• Morton RW et al. (2018). A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. British Journal of Sports Medicine 52(6):376-384.
  Used in: Protein target
• Nunes EA et al. (2022). Systematic review and meta-analysis of protein intake to support muscle mass and function in healthy adults. Journal of Cachexia, Sarcopenia and Muscle 13(2):795-810.
  Used in: Protein target
• Tagawa R, Watanabe D, Ito K et al. (2020). Dose-response relationship between protein intake and muscle mass increase: a systematic review and meta-analysis of randomized controlled trials. Nutrition Reviews 79(1):66-75.
  Used in: Protein target with little structured training
• Kato H, Suzuki K, Bannai M, Moore DR (2016). Protein requirements are elevated in endurance athletes after exercise as determined by the indicator amino acid oxidation method. PLoS One 11(6):e0157406.
  Used in: Protein target for endurance training
• Longland TM, Oikawa SY, Mitchell CJ, Devries MC, Phillips SM (2016). Higher compared with lower dietary protein during an energy deficit combined with intense exercise promotes greater lean mass gain and fat mass loss: a randomized trial. American Journal of Clinical Nutrition 103(3):738-746.
  Used in: Protein target on a cut
• Bauer J, Biolo G, Cederholm T et al. (2013). Evidence-based recommendations for optimal dietary protein intake in older people: a position paper from the PROT-AGE Study Group. Journal of the American Medical Directors Association 14(8):542-559.
  Used in: Protein floor from 65
• Deutz NE, Bauer JM, Barazzoni R et al. (2014). Protein intake and exercise for optimal muscle function with aging: recommendations from the ESPEN Expert Group. Clinical Nutrition 33(6):929-936.
  Used in: Protein floor from 65
• Rafii M, Chapman K, Owens J et al. (2015). Dietary protein requirement of female adults over 65 years determined by the indicator amino acid oxidation technique is higher than current recommendations. Journal of Nutrition 145(1):18-24.
  Used in: Protein floor from 65
• Rafii M, Chapman K, Elango R et al. (2016). Dietary protein requirement of men over 65 years old determined by the indicator amino acid oxidation technique is higher than the current estimated average requirement. Journal of Nutrition 146(4):681-687.
  Used in: Protein floor from 65
• Hevia-Larraín V, Gualano B, Longobardi I et al. (2021). High-protein plant-based diet versus a protein-matched omnivorous diet to support resistance training adaptations: a comparison between habitual vegans and omnivores. Sports Medicine 51(6):1317-1330.
  Used in: Protein target on a plant diet
• Mozaffarian D, Agarwal M, Aggarwal M et al. (2025). Nutritional priorities to support GLP-1 therapy for obesity: a joint advisory from the American College of Lifestyle Medicine, the American Society for Nutrition, the Obesity Medicine Association, and The Obesity Society. American Journal of Clinical Nutrition 122(1):344-367.
  Used in: Protein floor and ceiling on a GLP-1
• Kidney Disease: Improving Global Outcomes CKD Work Group (2024). KDIGO 2024 clinical practice guideline for the evaluation and management of chronic kidney disease. Kidney International 105(4S):S117-S314.
  Used in: Protein target with kidney disease, Supplements: whey
• US Department of Agriculture and US Department of Health and Human Services. Dietary Guidelines for Americans, 2025-2030.
  Used in: Protein target with little structured training
• Jäger R et al. (2017). International Society of Sports Nutrition position stand: protein and exercise. Journal of the International Society of Sports Nutrition 14:20.
  Used in: Protein target
• Antonio J et al. (2015). A high protein diet (3.4 g/kg/d) combined with a heavy resistance training program improves body composition in healthy trained men and women. Journal of the International Society of Sports Nutrition 12:39.
  Used in: Protein target when bulking
• Tarnopolsky MA et al. (1992). Evaluation of protein requirements for trained strength athletes. Journal of Applied Physiology 73(5):1986-1995.
  Used in: Protein target
• Thomas DT, Erdman KA, Burke LM (2016). Position of the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and athletic performance. Journal of the Academy of Nutrition and Dietetics 116(3):501-528.
  Used in: Carb minimum in your plan
• Roberts BM et al. (2020). Nutritional recommendations for physique athletes. Journal of Human Kinetics 71:79-108.
  Used in: Carb minimum for lifting
• Ruiz-Castellano C, Espinar S, Contreras C, Mata F, Aragon AA, Martínez-Sanz JM (2021). Achieving an optimal fat loss phase in resistance-trained athletes: a narrative review. Nutrients 13(9):3255.
  Used in: Carb minimum for lifting
• Henselmans M, Vårvik FT, Izquierdo M (2026). The effect of carbohydrate intake on muscle hypertrophy: a systematic review and meta-analysis. Sports Medicine 56(3):691-702.
  Used in: How carbs and fat are split
• World Health Organization (2015). Guideline: sugars intake for adults and children.
  Used in: Sugar limit: a tenth of calories. WHO sets it for free sugars; Vitals counts all sugar, so it is stricter
• Whittaker J, Wu K (2021). Low-fat diets and testosterone in men: systematic review and meta-analysis of intervention studies. Journal of Steroid Biochemistry and Molecular Biology 210:105878.
  Used in: Fat minimum in your plan
• Murphy C, Koehler K (2022). Energy deficiency impairs resistance training gains in lean mass but not strength: a meta-analysis and meta-regression. Scandinavian Journal of Medicine and Science in Sports 32(1):125-137.
  Used in: Largest daily deficit in your plan
• Loucks AB, Thuma JR (2003). Luteinizing hormone pulsatility is disrupted at a threshold of energy availability in regularly menstruating women. Journal of Clinical Endocrinology and Metabolism 88(1):297-311.
  Used in: Low energy warning in your plan
• Eisa N, Barood O (2026). Lean mass changes with incretin therapy versus lifestyle intervention: a systematic review and meta-analysis of randomised controlled trials. Diabetes, Obesity and Metabolism 28(6):4818-4827.
  Used in: Protein minimum on a GLP-1
• Deurenberg P, Weststrate JA, Seidell JC (1991). Body mass index as a measure of body fatness: age- and sex-specific prediction formulas. British Journal of Nutrition 65(2):105-114.
  Used in: Body fat guess when none is entered
• Byrne NM et al. (2018). Intermittent energy restriction improves weight loss efficiency in obese men: the MATADOR study. International Journal of Obesity 42(2):129-138.
  Used in: Diet break suggestion
• Peos JJ et al. (2021). Continuous versus intermittent dieting for fat loss and fat-free mass retention in resistance-trained adults: the ICECAP trial. Medicine and Science in Sports and Exercise 53(8):1685-1698.
  Used in: Diet break suggestion
• Siedler MR, Lewis MH, Trexler ET et al. (2023). The effects of intermittent diet breaks during 25% energy restriction on body composition and resting metabolic rate in resistance-trained females: a randomized controlled trial. Journal of Human Kinetics 86:117-132.
  Used in: Diet break suggestion
• Noakes TD, Prins PJ, Buga A, D'Agostino DP, Volek JS, Koutnik AP (2026). Carbohydrate ingestion on exercise metabolism and physical performance. Endocrine Reviews 47(2):191-243. PMID 41562187.
  Used in: Fuel before and during training
• Burke LM, Ross ML, Garvican-Lewis LA et al. (2017). Low carbohydrate, high fat diet impairs exercise economy and negates the performance benefit from intensified training in elite race walkers. Journal of Physiology 595(9):2785-2807.
  Used in: Fuel before and during training
• Helms ER et al. (2014). A systematic review of dietary protein during caloric restriction in resistance trained lean athletes: a case for higher intakes. International Journal of Sport Nutrition and Exercise Metabolism 24(2):127-138.
  Used in: Protein limit when cutting
• Iraki J et al. (2019). Nutrition recommendations for bodybuilders in the off-season: a narrative review. Sports 7(7):154.
  Used in: Protein limit when maintaining or bulking
• Areta JL, Burke LM, Ross ML et al. (2013). Timing and distribution of protein ingestion during prolonged recovery from resistance exercise alters myofibrillar protein synthesis. Journal of Physiology 591(9):2319-2331.
  Used in: Insights: skipped meals
• Mamerow MM, Mettler JA, English KL et al. (2014). Dietary protein distribution positively influences 24-h muscle protein synthesis in healthy adults. Journal of Nutrition 144(6):876-880.
  Used in: Insights: skipped meals
• Hudson JL, Bergia RE, Campbell WW (2020). Protein distribution and muscle-related outcomes: does the evidence support the concept? Nutrients 12(5):1441.
  Used in: Insights: skipped meals

Micronutrients

• National Academies, Food and Nutrition Board. Dietary Reference Intakes summary tables (RDA, AI and upper limits).
  Used in: Every vitamin and mineral target and upper limit
• NIH Office of Dietary Supplements. Health professional fact sheets.
  Used in: Vitamin and mineral targets, what each one does, sick day vitamin C, the vitamin and mineral supplement notes
• National Academies (2005). Dietary Reference Intakes for Water, Potassium, Sodium, Chloride, and Sulfate.
  Used in: Water target
• National Academies of Sciences, Engineering, and Medicine (2019). Dietary Reference Intakes for Sodium and Potassium.
  Used in: Potassium and sodium targets, the sodium heads-up after a log and From your logs on Me
• Kerksick CM et al. (2018). ISSN exercise and sports nutrition review update: research and recommendations. Journal of the International Society of Sports Nutrition 15:38.
  Used in: Sodium limit on training days
• European Union (2012). Commission Regulation (EU) No 432/2012, list of permitted health claims (vitamin C and intense exercise).
  Used in: Extra vitamin C on heavy training weeks
• NIH Office of Dietary Supplements (2022). Potassium Fact Sheet.
  Used in: Nutrient gaps: Potassium
• US Office of Disease Prevention and Health Promotion (2024). Where to Find the Nutrients Americans Miss.
  Used in: Nutrient gaps: Potassium, Vitamin D, Calcium
• Sacks et al., New England Journal of Medicine (2001). Reduced Salt and the DASH Diet on Blood Pressure.
  Used in: Nutrient gaps: Potassium
• National Academies of Sciences, Engineering, and Medicine (2019). Dietary Reference Intakes for Sodium and Potassium.
  Used in: Nutrient gaps: Potassium
• NIH Office of Dietary Supplements (2025). Vitamin D Fact Sheet.
  Used in: Nutrient gaps: Vitamin D
• Ikonte et al., Nutrients (2019). Micronutrient Inadequacy in Short Sleep: Analysis of the NHANES 2005-2016.
  Used in: Nutrient gaps: Vitamin D, Vitamin E, Vitamin K, Magnesium, Vitamin C, Vitamin A, Calcium, Zinc, Folate, Vitamin B6
• NIH Office of Dietary Supplements (2022). Choline Fact Sheet.
  Used in: Nutrient gaps: Choline
• Wallace and Fulgoni, Journal of the American College of Nutrition (2016). Assessment of Total Choline Intakes in the United States.
  Used in: Nutrient gaps: Choline
• Cowan et al., Current Developments in Nutrition (2019). Total Usual Micronutrient Intakes by Food Security Status.
  Used in: Nutrient gaps: Choline, Vitamin K, Magnesium, Vitamin A
• NIH Office of Dietary Supplements (2021). Vitamin E Fact Sheet.
  Used in: Nutrient gaps: Vitamin E
• Bird et al., Nutrients (2017). Risk of Deficiency in Multiple Concurrent Micronutrients.
  Used in: Nutrient gaps: Vitamin E, Vitamin C, Iron, Vitamin B12, Zinc, Vitamin B6
• NIH Office of Dietary Supplements (2021). Vitamin K Fact Sheet.
  Used in: Nutrient gaps: Vitamin K
• NIH Office of Dietary Supplements (2022). Magnesium Fact Sheet.
  Used in: Nutrient gaps: Magnesium
• Jackson et al., Nutrients (2018). Magnesium Intake in US Older Adults.
  Used in: Nutrient gaps: Magnesium
• NIH Office of Dietary Supplements (2021). Vitamin C Fact Sheet.
  Used in: Nutrient gaps: Vitamin C
• Reider et al., Nutrients (2020). Inadequacy of Immune Health Nutrients in US Adults.
  Used in: Nutrient gaps: Vitamin C, Vitamin A
• NIH Office of Dietary Supplements (2022). Vitamin A Fact Sheet.
  Used in: Nutrient gaps: Vitamin A
• NIH Office of Dietary Supplements (2024). Calcium Fact Sheet.
  Used in: Nutrient gaps: Calcium
• US Departments of Agriculture and of Health and Human Services (2020). Dietary Guidelines for Americans, 2020 to 2025.
  Used in: Nutrient gaps: Calcium, Iron
• Yu et al., Nutrients (2024). Trends in Calcium Intake in the US Population.
  Used in: Nutrient gaps: Calcium
• Tawfik et al., JAMA Network Open (2024). Absolute and Functional Iron Deficiency in the US, 2017-2020.
  Used in: Nutrient gaps: Iron
• NIH Office of Dietary Supplements (2023). Iron Fact Sheet.
  Used in: Nutrient gaps: Iron
• Cheng et al., BMC Pregnancy and Childbirth (2025). Some subgroups of U.S. childbearing women are still at risk of iodine deficiency in the 21st century: a cross-sectional analysis of NHANES 2001-2020.
  Used in: Nutrient gaps: Iodine
• Herrick et al., Nutrients (2018). Iodine Status and Consumption of Key Iodine Sources in the U.S. Population with Special Attention to Reproductive Age Women.
  Used in: Nutrient gaps: Iodine
• NIH Office of Dietary Supplements (2024). Iodine Fact Sheet.
  Used in: Nutrient gaps: Iodine
• US Centers for Disease Control and Prevention (2012). Second National Report on Biochemical Indicators.
  Used in: Nutrient gaps: Iodine
• NIH Office of Dietary Supplements (2025). Vitamin B12 Fact Sheet.
  Used in: Nutrient gaps: Vitamin B12
• Allen, American Journal of Clinical Nutrition (2009). How Common Is Vitamin B12 Deficiency?.
  Used in: Nutrient gaps: Vitamin B12
• NIH Office of Dietary Supplements (2022). Zinc Fact Sheet.
  Used in: Nutrient gaps: Zinc
• NIH Office of Dietary Supplements (2025). Folate Fact Sheet.
  Used in: Nutrient gaps: Folate
• US Centers for Disease Control and Prevention (2024). Folic Acid and Birth Defects.
  Used in: Nutrient gaps: Folate
• NIH Office of Dietary Supplements (2023). Vitamin B6 Fact Sheet.
  Used in: Nutrient gaps: Vitamin B6

Training

• Schoenfeld BJ, Ogborn D, Krieger JW (2017). Dose-response relationship between weekly resistance training volume and increases in muscle mass: a systematic review and meta-analysis. Journal of Sports Sciences 35(11):1073-1082.
  Used in: Balance chart on Train
• Baz-Valle E et al. (2022). A systematic review of the effects of different resistance training volumes on muscle hypertrophy. Journal of Human Kinetics 81:199-210.
  Used in: Balance chart on Train
• Schoenfeld BJ, Ogborn D, Krieger JW (2016). Effects of resistance training frequency on measures of muscle hypertrophy: a systematic review and meta-analysis. Sports Medicine 46(11):1689-1697.
  Used in: Insights: an area trained once in 2 weeks
• Epley B (1985). Poundage chart. Boyd Epley Workout.
  Used in: Estimated one rep max, best lifts
• Reynolds JM, Gordon TJ, Robergs RA (2006). Prediction of one repetition maximum strength from multiple repetition maximum testing and anthropometry. Journal of Strength and Conditioning Research 20(3):584-592.
  Used in: Estimated one rep max: a set past 10 reps counts as 10
• Rippetoe M (2011). Starting Strength, 3rd edition. The Aasgaard Company.
  Used in: Warm-up sets
• Haff GG, Triplett NT, eds. (2016). Essentials of Strength Training and Conditioning, 4th edition. NSCA, Human Kinetics.
  Used in: Warm-up sets

Body and fitness

• Kodama S et al. (2009). Cardiorespiratory fitness as a quantitative predictor of all-cause mortality and cardiovascular events in healthy men and women: a meta-analysis. JAMA 301(19):2024-2035.
  Used in: VO2 max and mortality
• Mandsager K et al. (2018). Association of cardiorespiratory fitness with long-term mortality among adults undergoing exercise treadmill testing. JAMA Network Open 1(6):e183605.
  Used in: VO2 max and mortality
• Kaminsky LA, Arena R, Myers J (2015). Reference standards for cardiorespiratory fitness measured with cardiopulmonary exercise testing: data from the Fitness Registry and the Importance of Exercise National Database. Mayo Clinic Proceedings 90(11):1515-1523.
  Used in: VO2 max bands (Cooper Clinic norms, Table 3)
• Kouri EM et al. (1995). Fat-free mass index in users and nonusers of anabolic-androgenic steroids. Clinical Journal of Sport Medicine 5(4):223-228.
  Used in: FFMI formula, and 25 as the usual drug-free limit for men
• Schutz Y, Kyle UUG, Pichard C (2002). Fat-free mass index and fat mass index percentiles in Caucasians aged 18-98 y. International Journal of Obesity 26(7):953-960.
  Used in: FFMI: what is average for men and women

Recovery and sleep

• Plews DJ, Laursen PB, Stanley J, Kilding AE, Buchheit M (2013). Training adaptation and heart rate variability in elite endurance athletes: opening the door to effective monitoring. Sports Medicine 43(9):773-781.
  Used in: Recovery: HRV and resting heart rate
• Buchheit M (2014). Monitoring training status with HR measures: do all roads lead to Rome? Frontiers in Physiology 5:73.
  Used in: Recovery: HRV and resting heart rate
• Fullagar HHK, Skorski S, Duffield R, Hammes D, Coutts AJ, Meyer T (2015). Sleep and athletic performance: the effects of sleep loss on exercise performance, and physiological and cognitive responses to exercise. Sports Medicine 45(2):161-186.
  Used in: Recovery: short sleep
• Gabbett TJ (2016). The training-injury prevention paradox: should athletes be training smarter and harder? British Journal of Sports Medicine 50(5):273-280.
  Used in: Recovery: training load spike
• Garthe I, Raastad T, Refsnes PE, Koivisto A, Sundgot-Borgen J (2011). Effect of two different weight-loss rates on body composition and strength and power-related performance in elite athletes. International Journal of Sport Nutrition and Exercise Metabolism 21(2):97-104.
  Used in: Recovery: weight dropping too fast
• Areta JL, Burke LM, Camera DM et al. (2014). Reduced resting skeletal muscle protein synthesis is rescued by resistance exercise and protein ingestion following short-term energy deficit. American Journal of Physiology: Endocrinology and Metabolism 306(8):E989-E997.
  Used in: Recovery on a cut, protein target when cutting
• Haghayegh S, Khoshnevis S, Smolensky MH, Diller KR, Castriotta RJ (2019). Before-bedtime passive body heating by warm shower or bath to improve sleep: a systematic review and meta-analysis. Sleep Medicine Reviews 46:124-135.
  Used in: Recovery: sauna or heat in the evening
• Hussain J, Cohen M (2018). Clinical effects of regular dry sauna bathing: a systematic review. Evidence-Based Complementary and Alternative Medicine 2018:1857413.
  Used in: Recovery: sauna
• Machado AF, Ferreira PH, Micheletti JK et al. (2016). Can water temperature and immersion time influence the effect of cold water immersion on muscle soreness? A systematic review and meta-analysis. Sports Medicine 46(4):503-514.
  Used in: Recovery: cold plunge after training, How do you feel: an ice bath eases soreness
• Pietilä J, Helander E, Korhonen I, Myllymäki T, Kujala UM, Lindholm H (2018). Acute effect of alcohol intake on cardiovascular autonomic regulation during the first hours of sleep in a large real-world sample of Finnish employees. JMIR Mental Health 5(1):e23.
  Used in: Recovery: alcohol and HRV
• Ebrahim IO, Shapiro CM, Williams AJ, Fenwick PB (2013). Alcohol and sleep I: effects on normal sleep. Alcoholism: Clinical and Experimental Research 37(4):539-549.
  Used in: Recovery: alcohol and sleep
• Crispim CA, Zimberg IZ, dos Reis BG et al. (2011). Relationship between food intake and sleep pattern in healthy individuals. Journal of Clinical Sleep Medicine 7(6):659-664.
  Used in: Recovery: late large meals
• St-Onge MP, Mikic A, Pietrolungo CE (2016). Effects of diet on sleep quality. Advances in Nutrition 7(5):938-949.
  Used in: Recovery: late large meals
• Watson NF, Badr MS, Belenky G et al. (2015). Recommended amount of sleep for a healthy adult: a joint consensus statement of the American Academy of Sleep Medicine and Sleep Research Society. Sleep 38(6):843-844.
  Used in: Recovery: sleep amount
• Hirshkowitz M, Whiton K, Albert SM et al. (2015). National Sleep Foundation's sleep time duration recommendations. Sleep Health 1(1):40-43.
  Used in: Recovery: sleep amount
• Phillips AJK, Clerx WM, O'Brien CS et al. (2017). Irregular sleep/wake patterns are associated with poorer academic performance and delayed circadian and sleep/wake timing. Scientific Reports 7:3216.
  Used in: Recovery: steady bedtime
• Windred DP, Burns AC, Lane JM et al. (2024). Sleep regularity is a stronger predictor of mortality risk than sleep duration: a prospective cohort study. Sleep 47(1):zsad253.
  Used in: Recovery: steady bedtime

How do you feel

• Hemilä H, Chalker E (2013). Vitamin C for preventing and treating the common cold. Cochrane Database of Systematic Reviews CD000980.
  Used in: How do you feel, sick: vitamin C once a cold has begun
• Hemilä H (2011). Zinc lozenges may shorten the duration of colds: a systematic review. Open Respiratory Medicine Journal 5:51-58.
  Used in: How do you feel, sick: zinc dose
• Hemilä H (2017). Zinc lozenges and the common cold: a meta-analysis comparing zinc acetate and zinc gluconate, and the role of zinc dosage. JRSM Open 8(5):2054270417694291.
  Used in: How do you feel, sick: zinc dose
• Institute of Medicine (2001). Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc.
  Used in: How do you feel, sick: the US zinc limit
• EFSA. Tolerable upper intake levels for vitamins and minerals, summary table (zinc: Scientific Committee on Food, 2002).
  Used in: How do you feel, sick: the European zinc limit
• Weidner TG et al. (1998). The effect of exercise training on the severity and duration of a viral upper respiratory illness. Medicine and Science in Sports and Exercise 30(11):1578-1583.
  Used in: How do you feel, sick: training with a head cold
• Primos WA Jr (1996). Sports and exercise during acute illness: recommending the right course for patients. Physician and Sportsmedicine 24(1):44-52.
  Used in: How do you feel, sick: above the neck
• Ranchordas MK et al. (2017). Antioxidants for preventing and reducing muscle soreness after exercise. Cochrane Database of Systematic Reviews CD009789.
  Used in: How do you feel, sore: tart cherry and other antioxidants
• Lv ZT, Zhang JM, Zhu WT (2020). Omega-3 polyunsaturated fatty acid supplementation for reducing muscle soreness after eccentric exercise: a systematic review and meta-analysis of randomized controlled trials. BioMed Research International 2020:8062017.
  Used in: How do you feel, sore: omega-3
• Fang W, Nasir Y (2021). The effect of curcumin supplementation on recovery following exercise-induced muscle damage and delayed-onset muscle soreness. Phytotherapy Research 35(4):1768-1781.
  Used in: How do you feel, sore: curcumin
• Northeast B, Clifford T (2021). The effect of creatine supplementation on markers of exercise-induced muscle damage. International Journal of Sport Nutrition and Exercise Metabolism 31(3):276-291.
  Used in: How do you feel, sore: creatine
• Fedewa MV et al. (2019). Effect of branched-chain amino acid supplementation on muscle soreness following exercise: a meta-analysis. International Journal for Vitamin and Nutrition Research 89(5-6):348-356.
  Used in: How do you feel, sore: BCAAs
• Wiewelhove T et al. (2019). A meta-analysis of the effects of foam rolling on performance and recovery. Frontiers in Physiology 10:376.
  Used in: How do you feel, sore: foam rolling
• Al Khatib HK et al. (2017). The effects of partial sleep deprivation on energy balance: a systematic review and meta-analysis. European Journal of Clinical Nutrition 71(5):614-624.
  Used in: How do you feel, slept badly: extra calories
• Zhu B et al. (2019). Effects of sleep restriction on metabolism-related parameters in healthy adults: a comprehensive review and meta-analysis of randomized controlled trials. Sleep Medicine Reviews 45:18-30.
  Used in: How do you feel, slept badly: extra calories, leptin and ghrelin
• Spaeth AM, Dinges DF, Goel N (2013). Effects of experimental sleep restriction on weight gain, caloric intake, and meal timing in healthy adults. Sleep 36(7):981-990.
  Used in: How do you feel, slept badly: eating late in the evening
• Craven J et al. (2022). Effects of acute sleep loss on physical performance: a systematic and meta-analytical review. Sports Medicine 52(11):2669-2690.
  Used in: How do you feel, slept badly: what suffers, and morning versus later

Sauna and cold

• Kukkonen-Harjula K et al. (1989). Haemodynamic and hormonal responses to heat exposure in a Finnish sauna bath. European Journal of Applied Physiology 58(5):543-550.
  Used in: Sauna: what happens to the body
• Podstawski R et al. (2019). Correlations between repeated use of dry sauna for 4 x 10 minutes, physiological parameters, anthropometric features, and body composition in young sedentary and overweight men. BioMed Research International 2019:7535140.
  Used in: Sauna: sweat and water to drink
• Pilch W et al. (2014). Comparison of physiological reactions and physiological strain in healthy men under heat stress in dry and steam heat saunas. Biology of Sport 31(2):145-149.
  Used in: Sauna and steam: sweat and water to drink
• Laukkanen T et al. (2018). Acute effects of sauna bathing on cardiovascular function. Journal of Human Hypertension 32(2):129-138.
  Used in: Sauna: blood pressure, safety notes
• Laukkanen T et al. (2015). Association between sauna bathing and fatal cardiovascular and all-cause mortality events. JAMA Internal Medicine 175(4):542-548.
  Used in: Sauna: what happens to the body
• Hannuksela ML, Ellahham S (2001). Benefits and risks of sauna bathing. American Journal of Medicine 110(2):118-126.
  Used in: Sauna safety notes
• Kukkonen-Harjula K, Kauppinen K (2006). Health effects and risks of sauna bathing. International Journal of Circumpolar Health 65(3):195-205.
  Used in: Sauna safety notes
• Milunsky A, Ulcickas M, Rothman KJ, Willett W, Jick SS, Jick H (1992). Maternal heat exposure and neural tube defects. JAMA 268(7):882-885.
  Used in: Sauna and hot tub safety notes: pregnancy
• US Consumer Product Safety Commission. CPSC warns of hot tub temperatures. News release.
  Used in: Hot tub safety notes: 40 °C (104 °F) limit, pregnancy, alcohol
• Tipton MJ et al. (2017). Cold water immersion: kill or cure? Experimental Physiology 102(11):1335-1355.
  Used in: Cold plunge: cold shock, safety notes
• Šrámek P et al. (2000). Human physiological responses to immersion into water of different temperatures. European Journal of Applied Physiology 81(5):436-442.
  Used in: Cold plunge: what happens to the body
• Roberts LA et al. (2015). Post-exercise cold water immersion attenuates acute anabolic signalling and long-term adaptations in muscle to strength training. Journal of Physiology 593(18):4285-4301.
  Used in: Cold plunge after lifting, How do you feel: an ice bath blunts muscle growth
• Buijze GA et al. (2016). The effect of cold showering on health and work: a randomized controlled trial. PLoS One 11(9):e0161749.
  Used in: Cold shower: what happens to the body
• Faulkner SH et al. (2017). The effect of passive heating on heat shock protein 70 and interleukin-6: a possible treatment tool for metabolic diseases? Temperature 4(3):292-304.
  Used in: Hot tub calories
• Giraud et al. (2024). Mechanism involved of post-exercise cold water immersion: blood redistribution and increased energy expenditure. Temperature.
  Used in: Cold plunge calories

Gut

• McDonald D et al. (2018). American Gut: an open platform for citizen science microbiome research. mSystems 3(3):e00031-18.
  Used in: Gut: plants per week
• Wastyk HC et al. (2021). Gut-microbiota-targeted diets modulate human immune status. Cell 184(16):4137-4153.
  Used in: Gut: fermented foods
• Institute of Medicine (2005). Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids.
  Used in: Gut: fiber target, and fiber after a log and in From your logs on Me
• Nandhra GK, Chaichanavichkij P, Birch M, Scott SM (2023). Gastrointestinal transit times in health as determined using ingestible capsule systems: a systematic review. Journal of Clinical Medicine 12(16):5272.
  Used in: Gut: how long after a food symptoms are linked
• NIDDK. Lactose intolerance: symptoms and causes.
  Used in: Gut: how soon symptoms can start

Food checks

• UK Food Standards Agency and Department of Health (2016). Guide to creating a front of pack (FoP) nutrition label for pre-packed products.
  Used in: Product check: high and low fat, sugar and salt
• European Union (2006). Regulation (EC) No 1924/2006 on nutrition and health claims made on foods, annex of permitted nutrition claims.
  Used in: Product check: high protein and high fiber
• Moore DR et al. (2009). Ingested protein dose response of muscle and albumin protein synthesis after resistance exercise in young men. American Journal of Clinical Nutrition 89(1):161-168.
  Used in: Food detail: protein per meal
• Witard OC et al. (2014). Myofibrillar muscle protein synthesis rates subsequent to a meal in response to increasing doses of whey protein at rest and after resistance exercise. American Journal of Clinical Nutrition 99(1):86-95.
  Used in: Food detail: protein per meal
• Moore DR et al. (2015). Protein ingestion to stimulate myofibrillar protein synthesis requires greater relative protein intakes in healthy older versus younger men. Journals of Gerontology Series A 70(1):57-62.
  Used in: Food detail: protein per meal for older adults
• FAO (2013). Dietary protein quality evaluation in human nutrition. FAO Food and Nutrition Paper 92.
  Used in: Food detail: complete and incomplete protein
• Sacks FM et al. (2017). Dietary fats and cardiovascular disease: a presidential advisory from the American Heart Association. Circulation 136(3):e1-e23.
  Used in: Food detail: saturated fat
• EFSA Panel on Dietetic Products, Nutrition and Allergies (2012). Scientific opinion on the tolerable upper intake level of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and docosapentaenoic acid (DPA). EFSA Journal 10(7):2815.
  Used in: Food detail: omega-3
• EFSA Panel on Dietetic Products, Nutrition and Allergies (2010). Scientific opinion on dietary reference values for fats. EFSA Journal 8(3):1461.
  Used in: Food detail: omega-3 daily amount
• Gardiner C, Weakley J, Burke LM et al. (2023). The effect of caffeine on subsequent sleep: a systematic review and meta-analysis. Sleep Medicine Reviews 69:101764.
  Used in: Food detail: caffeine and sleep, Supplements: caffeine, 9 hours before bed
• Drake C et al. (2013). Caffeine effects on sleep taken 0, 3, or 6 hours before going to bed. Journal of Clinical Sleep Medicine 9(11):1195-1200.
  Used in: Food detail: caffeine and sleep
• Institute of Medicine (2001). Caffeine for the Sustainment of Mental Task Performance.
  Used in: Food detail: how long caffeine lasts
• International Agency for Research on Cancer (WHO). IARC Monographs: list of classifications.
  Used in: Product check: processed meat, aspartame, BHA and potassium bromate
• Bouvard V, Loomis D, Guyton KZ et al. (2015). Carcinogenicity of consumption of red and processed meat. Lancet Oncology 16(16):1599-1600.
  Used in: Product check: nitrites and processed meat
• US Code of Federal Regulations, 9 CFR 317.17. Labeling of cured products, nitrate and nitrite.
  Used in: Product check: celery powder in "uncured" meat
• US Food and Drug Administration. Trans fat.
  Used in: Product check: partially hydrogenated oil
• Mozaffarian D, Katan MB, Ascherio A, Stampfer MJ, Willett WC (2006). Trans fatty acids and cardiovascular disease. New England Journal of Medicine 354(15):1601-1613.
  Used in: Product check: partially hydrogenated oil
• US Food and Drug Administration. Added sugars on the Nutrition Facts label.
  Used in: Product check: high-fructose corn syrup
• World Health Organization (2023). Use of non-sugar sweeteners: WHO guideline.
  Used in: Product check: artificial sweeteners
• World Health Organization (2023). Aspartame hazard and risk assessment results released. News release, 14 July 2023.
  Used in: Product check: aspartame
• European Union (2011). Regulation (EU) No 1169/2011 on the provision of food information to consumers.
  Used in: Product check: sugar alcohols (Annex III), sugar as the first ingredient (Article 18)
• US Code of Federal Regulations, 21 CFR 101.4. Food; designation of ingredients.
  Used in: Product check: sugar as the first ingredient
• McCann D, Barrett A, Cooper A et al. (2007). Food additives and hyperactive behaviour in 3-year-old and 8/9-year-old children in the community: a randomised, double-blinded, placebo-controlled trial. Lancet 370(9598):1560-1567.
  Used in: Product check: artificial colors
• European Union (2008). Regulation (EC) No 1333/2008 on food additives.
  Used in: Product check: the color warning (Annex V), potassium bromate not on the EU list
• US Food and Drug Administration. FD&C Red No. 3.
  Used in: Product check: Red No. 3
• European Commission (2022). Commission Regulation (EU) 2022/63 as regards the food additive titanium dioxide (E 171).
  Used in: Product check: titanium dioxide
• UK (1990). The Potassium Bromate (Prohibition as a Flour Improver) Regulations 1990, SI 1990/399.
  Used in: Product check: potassium bromate
• Chassaing B, Koren O, Goodrich JK et al. (2015). Dietary emulsifiers impact the mouse gut microbiota promoting colitis and metabolic syndrome. Nature 519(7541):92-96.
  Used in: Product check: emulsifiers
• Chassaing B, Compher C, Bonhomme B et al. (2022). Randomized controlled-feeding study of dietary emulsifier carboxymethylcellulose reveals detrimental impacts on the gut microbiota and metabolome. Gastroenterology 162(3):743-756.
  Used in: Product check: emulsifiers
• Kalantar-Zadeh K, Gutekunst L, Mehrotra R et al. (2010). Understanding sources of dietary phosphorus in the treatment of patients with chronic kidney disease. Clinical Journal of the American Society of Nephrology 5(3):519-530.
  Used in: Product check: added phosphates
• Monteiro CA, Cannon G, Levy RB et al. (2019). Ultra-processed foods: what they are and how to identify them. Public Health Nutrition 22(5):936-941.
  Used in: Product check: heavily processed
• Lane MM, Gamage E, Du S et al. (2024). Ultra-processed food exposure and adverse health outcomes: umbrella review of epidemiological meta-analyses. BMJ 384:e077310.
  Used in: Product check: heavily processed
• Open Food Facts. Open product database of packaged foods.
  Used in: Barcode scan: product nutrients and ingredients
• USDA Agricultural Research Service. FoodData Central.
  Used in: Food search, quick add foods and portion sizes

Supplements and peptides

• Levine M, Conry-Cantilena C, Wang Y et al. (1996). Vitamin C pharmacokinetics in healthy volunteers: evidence for a recommended dietary allowance. Proceedings of the National Academy of Sciences 93(8):3704-3709.
  Used in: Supplements: vitamin C
• CDC. About folic acid.
  Used in: Supplements: folate in pregnancy
• MRC Vitamin Study Research Group (1991). Prevention of neural tube defects: results of the Medical Research Council Vitamin Study. Lancet 338(8760):131-137.
  Used in: Supplements: folate in pregnancy
• US Preventive Services Task Force (2023). Folic acid supplementation to prevent neural tube defects: reaffirmation recommendation statement. JAMA 330(5):454-459.
  Used in: Supplements: folate in pregnancy
• Theuwissen E, Teunissen KJ, Spronk HM et al. (2013). Effect of low-dose supplements of menaquinone-7 (vitamin K2) on the stability of oral anticoagulant treatment: dose-response relationship in healthy volunteers. Journal of Thrombosis and Haemostasis 11(6):1085-1092.
  Used in: Supplements: vitamin K2 with a blood thinner
• Zwakenberg SR, de Jong PA, Bartstra JW et al. (2019). The effect of menaquinone-7 supplementation on vascular calcification in patients with diabetes: a randomized, double-blind, placebo-controlled trial. American Journal of Clinical Nutrition 110(4):883-890.
  Used in: Supplements: vitamin K2, heart and artery claims
• Skulas-Ray AC, Wilson PWF, Harris WS et al. (2019). Omega-3 fatty acids for the management of hypertriglyceridemia: a science advisory from the American Heart Association. Circulation 140(12):e673-e691.
  Used in: Supplements: omega-3 and triglycerides
• Halegoua-DeMarzio D, Navarro V, Ahmad J et al. (2023). Liver injury associated with turmeric: a growing problem. Ten cases from the Drug-Induced Liver Injury Network. American Journal of Medicine 136(2):200-206.
  Used in: Supplements: turmeric and the liver
• EFSA Panel on Food Additives and Nutrient Sources added to Food (2018). Scientific opinion on the safety of green tea catechins. EFSA Journal 16(4):5239.
  Used in: Supplements: green tea extract and the liver
• NCCIH. Ashwagandha: usefulness and safety.
  Used in: Supplements: ashwagandha safety
• NCCIH. In the news: berberine.
  Used in: Supplements: berberine in pregnancy and breastfeeding
• NCCIH. Probiotics: usefulness and safety.
  Used in: Supplements: probiotics are strain specific
• Franco JV, Trivisonno L, Sgarbossa NJ et al. (2023). Serenoa repens for the treatment of lower urinary tract symptoms due to benign prostatic enlargement. Cochrane Database of Systematic Reviews CD001423.
  Used in: Supplements: saw palmetto
• Jovanovski E, Yashpal S, Komishon A et al. (2018). Effect of psyllium (Plantago ovata) fiber on LDL cholesterol and alternative lipid targets, non-HDL cholesterol and apolipoprotein B: a systematic review and meta-analysis of randomized controlled trials. American Journal of Clinical Nutrition 108(5):922-932.
  Used in: Supplements: psyllium and cholesterol
• Shaw G, Lee-Barthel A, Ross ML, Wang B, Baar K (2017). Vitamin C-enriched gelatin supplementation before intermittent activity augments collagen synthesis. American Journal of Clinical Nutrition 105(1):136-143.
  Used in: Supplements: collagen with vitamin C before loading
• Kreider RB, Kalman DS, Antonio J et al. (2017). International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine. Journal of the International Society of Sports Nutrition 14:18.
  Used in: Supplements: creatine dose and loading
• Ribeiro F, Longobardi I, Perim P et al. (2021). Timing of creatine supplementation around exercise: a real concern? Nutrients 13(8):2844.
  Used in: Supplements: creatine, time of day
• Guest NS, VanDusseldorp TA, Nelson MT et al. (2021). International Society of Sports Nutrition position stand: caffeine and exercise performance. Journal of the International Society of Sports Nutrition 18(1):1.
  Used in: Supplements: caffeine, 3 to 6 mg per kg
• EFSA Panel on Dietetic Products, Nutrition and Allergies (2015). Scientific opinion on the safety of caffeine. EFSA Journal 13(5):4102.
  Used in: Supplements: caffeine, 400 mg a day and 200 mg in pregnancy
• US Food and Drug Administration. Spilling the beans: how much caffeine is too much?
  Used in: Supplements: caffeine, 400 mg a day
• Trexler ET, Smith-Ryan AE, Stout JR et al. (2015). International Society of Sports Nutrition position stand: beta-alanine. Journal of the International Society of Sports Nutrition 12:30.
  Used in: Supplements: beta-alanine
• Herxheimer A, Petrie KJ (2002). Melatonin for the prevention and treatment of jet lag. Cochrane Database of Systematic Reviews CD001520.
  Used in: Supplements: melatonin dose and timing
• NHS. Melatonin: about melatonin.
  Used in: Supplements: melatonin is prescription-only in the UK
• Novo Nordisk. Wegovy (semaglutide) prescribing information. US label on DailyMed.
  Used in: Peptides: semaglutide safety notes, weekly dosing
• US Food and Drug Administration (2024). FDA alerts health care providers, compounders and patients of dosing errors associated with compounded injectable semaglutide products.
  Used in: Peptides: compounded semaglutide overdoses
• Eli Lilly. Zepbound (tirzepatide) prescribing information. US label on DailyMed.
  Used in: Peptides: tirzepatide safety notes, weekly dosing
• Look M et al. (2025). Body composition changes during weight reduction with tirzepatide in the SURMOUNT-1 study of adults with obesity or overweight. Diabetes, Obesity and Metabolism 27(5):2720-2729.
  Used in: Peptides: lean mass lost on tirzepatide
• Jastreboff AM et al. (2023). Triple-hormone-receptor agonist retatrutide for obesity: a phase 2 trial. New England Journal of Medicine 389(6):514-526.
  Used in: Peptides: retatrutide
• Jastreboff AM et al. (2026). Retatrutide, a triple hormone receptor agonist, for treatment of obesity. New England Journal of Medicine, published online 29 September 2026.
  Used in: Peptides: retatrutide, phase 3
• Garvey WT et al. (2025). Coadministered cagrilintide and semaglutide in adults with overweight or obesity. New England Journal of Medicine 393(7):635-647.
  Used in: Peptides: cagrilintide
• Theratechnologies. Egrifta (tesamorelin) prescribing information. US label on DailyMed.
  Used in: Peptides: tesamorelin
• Vyleesi (bremelanotide) prescribing information. US label on DailyMed.
  Used in: Peptides: PT-141 (bremelanotide)
• Nass R et al. (2008). Effects of an oral ghrelin mimetic on body composition and clinical outcomes in healthy older adults: a randomized trial. Annals of Internal Medicine 149(9):601-611.
  Used in: Peptides: MK-677 (ibutamoren)
• Vasireddi N et al. (2025). Emerging use of BPC-157 in orthopaedic sports medicine: a systematic review. HSS Journal 21(4):485-495.
  Used in: Peptides: BPC-157 evidence
• Valentino MA, Lin JE, Waldman SA (2010). Central and peripheral molecular targets for antiobesity pharmacotherapy. Clinical Pharmacology and Therapeutics 87(6):652-662.
  Used in: Peptides: AOD-9604 trial result
• Goldstein AL, Goldstein AL (2009). From lab to bedside: emerging clinical applications of thymosin alpha 1. Expert Opinion on Biological Therapy 9(5):593-608.
  Used in: Peptides: thymosin alpha-1
• Billon C et al. (2023). Synthetic ERRα/β/γ agonist induces an ERRα-dependent acute aerobic exercise response and enhances exercise capacity. ACS Chemical Biology 18(4):756-771.
  Used in: Peptides: SLU-PP-332
• US Food and Drug Administration. Certain bulk drug substances for use in compounding that may present significant safety risks.
  Used in: Peptides: BPC-157, TB-500, GHK-Cu, ipamorelin, CJC-1295, AOD-9604, MOTS-c, Epitalon, Semax
• World Anti-Doping Agency (2026). The 2026 Prohibited List.
  Used in: Peptides: banned in sport (BPC-157, TB-500, GH secretagogues)
• Hultman E, Söderlund K, Timmons JA et al. (1996). Muscle creatine loading in men. Journal of Applied Physiology 81(1):232-237.
  Used in: Supplements: creatine, loading or not
• Ashtary-Larky D et al. (2025). Creatine supplementation and resistance training: a comparison between novice and experienced lifters, a systematic review and dose-response meta-analysis. Journal of the International Society of Sports Nutrition 22(sup1):2586523.
  Used in: Supplements: creatine, lean mass with lifting
• Forbes SC, Candow DG, Ostojic SM et al. (2021). Meta-analysis examining the importance of creatine ingestion strategies on lean tissue mass and strength in older adults. Nutrients 13(6):1912.
  Used in: Supplements: creatine in older adults, dose
• Liu S et al. (2025). The impact of creatine supplementation associated with resistance training on muscular strength and lean tissue mass in the aged: a systematic review and meta-analysis. European Review of Aging and Physical Activity 22:26.
  Used in: Supplements: creatine in older adults
• Xu C et al. (2024). The effects of creatine supplementation on cognitive function in adults: a systematic review and meta-analysis. Frontiers in Nutrition 11:1424972.
  Used in: Supplements: creatine and the brain
• EFSA Panel on Nutrition, Novel Foods and Food Allergens (2024). Creatine and improvement in cognitive function: evaluation of a health claim. EFSA Journal 22(11):e9100.
  Used in: Supplements: creatine and the brain
• Candow DG et al. (2026). Creatine supplementation and the brain: have we put the cart before the horse? Journal of Dietary Supplements 23(2):175-204.
  Used in: Supplements: creatine and the brain
• Tsiaras A et al. (2026). The effect of creatine supplementation on kidney function: a systematic review and meta-analysis of randomized controlled trials. Journal of Renal Nutrition, online.
  Used in: Supplements: creatine, creatinine and the kidneys
• de Souza Almeida A et al. (2026). Impact of creatine supplementation on kidney health: a systematic review and meta-analysis. International Urology and Nephrology, online.
  Used in: Supplements: creatine, creatinine and the kidneys
• Antonio J, Candow DG, Forbes SC et al. (2021). Common questions and misconceptions about creatine supplementation: what does the scientific evidence really show? Journal of the International Society of Sports Nutrition 18:13.
  Used in: Supplements: creatine, water weight and safety
• Lopresti AL et al. (2026). Magnesium supplementation for sleep in adults: a systematic review of randomized controlled trials. Journal of Dietary Supplements 23(5):553-581.
  Used in: Supplements: magnesium and sleep
• Schuster J et al. (2025). Magnesium bisglycinate supplementation in healthy adults reporting poor sleep: a randomized, placebo-controlled trial. Nature and Science of Sleep 17:2027-2040.
  Used in: Supplements: magnesium and sleep
• Garrison SR, Korownyk CS, Kolber MR et al. (2020). Magnesium for skeletal muscle cramps. Cochrane Database of Systematic Reviews CD009402.
  Used in: Supplements: magnesium and cramps
• Gencer B, Djousse L, Al-Ramady OT et al. (2021). Effect of long-term marine omega-3 fatty acids supplementation on the risk of atrial fibrillation in randomized controlled trials of cardiovascular outcomes: a systematic review and meta-analysis. Circulation 144(25):1981-1990.
  Used in: Supplements: omega-3 over 1 g a day and atrial fibrillation
• Chen G, Qian ZM, Zhang J et al. (2024). Regular use of fish oil supplements and course of cardiovascular diseases: prospective cohort study. BMJ Medicine 3(1):e000451.
  Used in: Supplements: omega-3 in healthy people
• van der Schoot A, Drysdale C, Whelan K, Dimidi E (2022). The effect of fiber supplementation on chronic constipation in adults: an updated systematic review and meta-analysis of randomized controlled trials. American Journal of Clinical Nutrition 116(4):953-969.
  Used in: Supplements: psyllium for regularity
• Lam JR, Schneider JL, Zhao W, Corley DA (2013). Proton pump inhibitor and histamine 2 receptor antagonist use and vitamin B12 deficiency. JAMA 310(22):2435-2442.
  Used in: Supplements: B12 and acid reducers
• Aroda VR, Edelstein SL, Goldberg RB et al. (2016). Long-term metformin use and vitamin B12 deficiency in the Diabetes Prevention Program Outcomes Study. Journal of Clinical Endocrinology and Metabolism 101(4):1754-1761.
  Used in: Supplements: B12 and metformin
• Demay MB, Pittas AG, Bikle DD et al. (2024). Vitamin D for the prevention of disease: an Endocrine Society clinical practice guideline. Journal of Clinical Endocrinology and Metabolism 109(8):1907-1947.
  Used in: Supplements: vitamin D, who it is for and testing
• LeBoff MS, Chou SH, Ratliff KA et al. (2022). Supplemental vitamin D and incident fractures in midlife and older adults. New England Journal of Medicine 387(4):299-309.
  Used in: Supplements: vitamin D and fractures
• Waterhouse M, Ebeling PR, McLeod DSA et al. (2023). The effect of monthly vitamin D supplementation on fractures: a tertiary outcome from the population-based, double-blind, randomised, placebo-controlled D-Health trial. Lancet Diabetes and Endocrinology 11(5):324-332.
  Used in: Supplements: vitamin D and fractures
• Nault D, Machingo TA, Shipper AG et al. (2024). Zinc for prevention and treatment of the common cold. Cochrane Database of Systematic Reviews CD014914.
  Used in: Supplements: zinc and colds

Activity and calories

• Herrmann SD et al. (2024). 2024 Adult Compendium of Physical Activities: a third update of the energy costs of human activities. Journal of Sport and Health Science 13(1):6-12.
  Used in: Calories burned for workouts and activities, training calories in your plan
• Minetti AE, Moia C, Roi GS, Susta D, Ferretti G (2002). Energy cost of walking and running at extreme uphill and downhill slopes. Journal of Applied Physiology 93(3):1039-1046.
  Used in: Calories for walks and runs on hills
• Byrne NM et al. (2005). Metabolic equivalent: one size does not fit all. Journal of Applied Physiology 99(3):1112-1119.
  Used in: Training calories in your plan
• Shcherbina A et al. (2017). Accuracy in wrist-worn, sensor-based measurements of heart rate and energy expenditure in a diverse cohort. Journal of Personalized Medicine 7(2):3.
  Used in: Apple Health calories, why they are not added to your target
• Heymsfield SB, Thomas D, Martin CK et al. (2012). Energy content of weight loss: kinetic features during voluntary caloric restriction. Metabolism 61(7):937-943.
  Used in: Calories from your weigh-ins
• Hall KD, Chow CC (2011). Estimating changes in free-living energy intake and its confidence interval. American Journal of Clinical Nutrition 94(1):66-74.
  Used in: Calories from your weigh-ins: 28 days needed
• Scientific Advisory Committee on Nutrition (2011). Dietary Reference Values for Energy.
  Used in: Lowest activity level in your plan
• Pandolf KB, Givoni B, Goldman RF (1977). Predicting energy expenditure with loads while standing or walking very slowly. Journal of Applied Physiology 43(4):577-581.
  Used in: Cardio: carrying a vest or backpack
• Soule RG, Goldman RF (1969). Energy cost of loads carried on the head, hands, or feet. Journal of Applied Physiology 27(5):687-690.
  Used in: Cardio: ankle weights
• Soule RG, Goldman RF (1972). Terrain coefficients for energy cost prediction. Journal of Applied Physiology 32(5):706-708.
  Used in: Cardio: trail
• Lejeune TM, Willems PA, Heglund NC (1998). Mechanics and energetics of human locomotion on sand. Journal of Experimental Biology 201(13):2071-2080.
  Used in: Cardio: sand
• Tudor-Locke C, Bassett DR Jr (2004). How many steps/day are enough? Preliminary pedometer indices for public health. Sports Medicine 34(1):1-8.
  Used in: Activity level in your plan: the step bands
• Garber CE, Blissmer B, Deschenes MR et al. (2011). Quantity and quality of exercise for developing and maintaining cardiorespiratory, musculoskeletal, and neuromotor fitness in apparently healthy adults. Medicine and Science in Sports and Exercise 43(7):1334-1359.
  Used in: Activity: easy, moderate or hard from heart rate
• Tanaka H, Monahan KD, Seals DR (2001). Age-predicted maximal heart rate revisited. Journal of the American College of Cardiology 37(1):153-156.
  Used in: Activity: maximum heart rate for your age
• Bull FC, Al-Ansari SS, Biddle S et al. (2020). World Health Organization 2020 guidelines on physical activity and sedentary behaviour. British Journal of Sports Medicine 54(24):1451-1462.
  Used in: Activity: a hard minute counts as two moderate ones
• Cheung K, Hume P, Maxwell L (2003). Delayed onset muscle soreness: treatment strategies and performance factors. Sports Medicine 33(2):145-164.
  Used in: Activity: how long a session takes to recover from, How do you feel: soreness lasts two to four days
• Nédélec M, McCall A, Carling C, Legall F, Berthoin S, Dupont G (2012). Recovery in soccer: part I, post-match fatigue and time course of recovery. Sports Medicine 42(12):997-1015.
  Used in: Activity: contact and impact sports take longer

Outdoors

• Sawka MN et al., Med Sci Sports Exerc (2007). American College of Sports Medicine position stand: exercise and fluid replacement.
  Used in: Outside card on Activity, extra water for training in your plan
• Castellani JW et al., Med Sci Sports Exerc (2006). American College of Sports Medicine position stand: prevention of cold injuries during exercise.
  Used in: Outside card on Activity
• World Health Organization (2002). Global Solar UV Index: a practical guide.
  Used in: Outside card on Activity
• Twohig-Bennett C, Jones A, Environ Res (2018). The health benefits of the great outdoors: a systematic review and meta-analysis of greenspace exposure and health outcomes.
  Used in: Outside card on Activity
• Gascon M et al., Int J Hyg Environ Health (2017). Outdoor blue spaces, human health and well-being: a systematic review of quantitative studies.
  Used in: Outside card on Activity
• White MP et al., Sci Rep (2019). Spending at least 120 minutes a week in nature is associated with good health and wellbeing.
  Used in: Outside card on Activity
• Burns AC et al., J Affect Disord (2021). Time spent in outdoor light is associated with mood, sleep, and circadian rhythm-related outcomes.
  Used in: Outside card on Activity