by Jack Norris, RD, LD
- Vitamins and Minerals
- During Workouts
- After Workouts
- Carnosine and beta-Alanine
Many weightlifters think a vegan diet might be detrimental to their efforts because of the lower protein content of a typical vegan diet. Other weightlifters feel that a vegan diet enhances their training regimen by reducing fatigue and improving general health. Unfortunately, there are no studies looking directly at vegan weightlifters, but there is a fair amount of research that can be used to extrapolate to vegans.
While reading, keep in mind that weightlifting can be divided into two types:
- Bodybuilding to achieve the most noticeable muscles.
- Powerlifting to produce the largest amounts of strength.
Carbohydrates, fat, protein, and alcohol all provide energy. Resistance training, exercises where muscles push or pull against some force, is used to develop and maintain muscular strength and requires an increase in energy above that of sedentary individuals. The amounts vary depending upon training regimen, as well as other factors, including exercise efficiency, gender, non-exercise habits, and genetics. Because of the variation in needs, there is no one easy formula for caloric requirements; it is a matter of experimentation.
It is important to note that not eating enough calories to meet needs will tend to reduce muscle mass. Eating adequate calories spares muscle protein that would otherwise be used for energy. For a general ballpark figure, novice male weightlifters increased muscle mass and size, and lowered body fat, on a diet of about 18 calories/lb of body weight per day (3,240 calories/day for a 180-lb person) (Lemon 1992). In another study, highly trained male bodybuilders ate 22.7 calories/lb (4,086 calories/day for a 180-lb person) (Tarnopolsky, 1988).
The Institute of Medicine, which sets the RDAs, doesn’t recommend higher protein intakes for athletes. However, in a 2016 joint position paper on nutrition and athletic performance, the American College of Sports Medicine (ACSM), the Academy of Nutrition and Dietetics (AND), and Dietitians of Canada recommend higher protein intakes for athletes and also suggest that athletes should give some attention to timing of protein intake (Thomas, 2016). They don’t differentiate between strength and endurance athletes in making the following recommendations:
- Dietary protein intake necessary to support metabolic adaptation, repair, remodeling, and for protein turnover generally ranges from 1.2 to 2.0 g/kg/ day.
- Daily protein needs should be met with a meal plan providing a regular spread of moderate amounts of high-quality protein across the day and following strenuous training sessions. Muscle protein synthesis is maximized by consumption of 0.3 grams protein/kg body weight every three to five hours, including consumption of this amount within two hours following exercise.
However, there are still questions about optimal intake and timing of protein for athletes. A 2017 meta-analysis of the effects of protein intakes among strength athletes found that timing of protein intake was not important for gains in muscle mass and strength (Morton, 2018). They suggested that a daily protein intake of 1.6 g/kg/day, separated into 0.25 g/kg doses, was sufficient for muscle protein synthesis.
Legumes, soyfoods, quinoa, and wheat gluten (seitan) are the typical vegan foods highest in protein. It’s also possible for vegans to take a protein supplement. There are a number of vegan protein supplements, including soy-free supplements for those allergic to soy or who don’t want more soy in their diet. For a list of high-protein plant foods, see Protein and Amino Acid Content of Selected Plant Foods.
Research on Plant-Based Protein
Hevia-Larraín et al. (Brazil, 2021) studied changes in leg muscle strength and size among 19 male vegans and 19 male omnivores. The participants had to have followed their diet for at least one year. Participants’ protein intakes were increased to 1.6 g/kg of body weight per day, through supplemental soy protein for vegans or whey protein for omnivores, and they followed a lower-body resistance training program for 12 weeks. Muscle mass and size increased among both groups with no statistically significant differences. The authors cautioned that meeting 1.6 g/kg of protein per day would be difficult on a whole foods, plant-based diet and noted that the soy protein isolates the study participants were consuming had been stripped of any factors that might block protein absorption from whole plant foods. At the time this study was conducted, no other study had compared the effects of protein source between vegans and omnivores in response to exercise; therefore, this study suggests that 1.6 g/kg of protein is enough for vegans to match omnivores in gains of muscle strength and size but that much protein might not be required. The study by Conrado de Souza et al., described below, suggests that closer to 1.0 g/kg of protein might be enough.
Conrado de Souza et al. (2022, Brazil) compared the squat, handgrip strength, isometric deadlift strength, jumping, and maximum aerobic speed between a group of physically active, 18 to 40 year-old, male and female vegetarians (9 vegans, 23 lacto-ovo-vegetarians) and 26 omnivores. The only differences between the groups were that the vegetarians had higher “relative strength” and jumping scores, possibly as a function of weighing slightly less. This was apparently the first strength study that compared already-physically active vegetarians and omnivores. The vegetarians had a protein intake of 1.0 g/kg of body weight compared to 1.6 g/kg for the omnivores.
Monteyne et al. (2023) conducted a two-phase study comparing the muscle-building capacity of a high-protein, mycoprotein-supplemented vegan diet to a high-protein omnivorous diet:
In Phase 2, participants were placed on a 10-week program of resistance training. The omnivore group averaged 2.3 g/kg/day of protein while the vegan group averaged 2.1 g/kg/day of mycoprotein-supplemented plant protein. Both groups received creatine at doses of 25 g/day during week 1 and 5 g/day for the remaining weeks. Significant muscle growth occurred alongside considerable increases in strength (23% on average; range = 4%–88%) with no difference between groups. Participants in the vegan group reported having a harder time ingesting enough protein.
Mycoprotein is a fungal-derived dietary protein source. The habitual diet for the omnivore group at baseline was 1.5 g/kg/day of protein.
This study suggests that if vegans have a protein intake of 2.1 g/kg/day, their strength gains made on a resistance training program will be similar to meat-eaters at a similar level of protein. However, because these participants were taking creatine and supplementing with mycoprotein, an uncommon protein source, the results can’t necessarily be extrapolated to free-living vegans not doing such things.
Based on studies of endurance athletes, some researchers believe that fat is an important part of the athlete’s diet. Diets that are too low in fat (15 percent or less fat) may compromise immunity, reduce intramuscular fat stores (which could spare muscle protein), and reduce energy intake (Venkatraman, 2000). While this has not been studied in bodybuilders, the novice bodybuilders in Lemon et al.’s study received about 31 percent of their calories from fat and succeeded in increasing strength and muscle size (Lemon, 1992). Average fat intake for vegans is about 28 percent of calories (Appleby, 2002). Higher fat intakes might also reduce the chances of irregular menstrual cycles in women caused by low body fat.
Carbohydrates are the major fuel used during resistance exercise (Lemon, 1998). Some researchers recommend 6 g of carbohydrate/kg of body weight (2.7 g/lb) daily, or about 55 to 60 percent of total intake (Lambert, 2002). Vegan weightlifters who meet energy requirements and stay close to the protein and fat recommendations listed here would automatically eat enough carbohydrates.
Vitamins and Minerals
When food intake increases, as it should on a weightlifting regimen, vitamin and mineral intake will also naturally increase. Vitamin or mineral intake in excess of the RDA has not been studied in weightlifters. Vegan weightlifters should pay attention to the nutrients that are recommended for all vegans in Daily Needs, mainly vitamin B12, calcium, iodine, and vitamin D; there is no evidence that any of these nutrients are needed in larger amounts than what would normally be consumed in a typical, varied vegan diet.
Female bodybuilders, especially those who experience amenorrhea (loss of menstrual periods), should pay careful attention to getting enough calcium and vitamin D. The RDA for adults is 1,000 mg for calcium and 5 micrograms (200 International Units) for vitamin D. Some health professionals recommend a multivitamin of 50 to 100 percent of the RDA for all people. That could be more important for people restricting their caloric intake.
Carbohydrate supplementation during weight training may be beneficial for promoting higher quality training and perhaps improving muscle gain. Ingesting carbohydrates during resistance exercise has been shown to increase the number of sets and repetitions before exhaustion (Lambert, 2002). Fruit juice diluted at a rate of 1 part juice to 1 part water will provide a sugar content comparable to sports drinks.
Doi et al. (2001) found that eating a supplement of protein (10 g), carbohydrate (7 g), fat (3 g), and a third of the RDA for vitamins and minerals immediately after, versus 1.5 hours after light resistance exercise, may reduce nitrogen losses and increase resting metabolic rate (indicating that muscle mass may be preserved).
Creatine (also known as creatine monohydrate) is the only nutritional supplement that has been consistently shown to improve strength and muscle mass. The main benefit of creatine is thought to be due to its effect on reducing fatigue during repeated, short bursts of intense exercise (such as weightlifting, sprinting, soccer, rugby, and hockey); lower fatigue during sprinting and weightlifting means increased training and greater results (Casey, 2000).
Creatine is a component of phosphocreatine (PCr). PCr provides energy during short bursts of powerful exercise, by providing a phosphate for the production of adenosine triphosphate (ATP), which is the quickest source of energy in skeletal muscle. Depletion of PCr in muscle is associated with fatigue during such exercise (Shomrat, 2000).
Creatine can be synthesized in the body. It is also supplied in the diet by meat and fish. Supplementing with creatine has been shown to increase performance (Shomrat, 2000; Stone, 1999) especially in people whose creatine levels in muscle were initially on the lower side of normal (Casey, 2000).
Generally, a daily total of 20-30 g of creatine, broken up in smaller doses over the course of a day and taken for five to six days, has been shown to increase performance; there appears to be no benefit to taking this dose for longer than six days and after the initial “loading” phase, 2 g/day maintains creatine levels for at least one month (Casey, 2000). Lambert and Flynn (2002) suggest taking creatine only every other month to maximize its effects; they don’t specify whether they recommend a loading phase each time someone starts a new month of creatine, but from the context of their comments I’d guess they don’t find it necessary.
Creatine Supplementation Trials in Vegetarians
Vegetarians have lower levels of creatine in their blood, urine, and red blood cells (Shomrat, 2000; Delanghe, 1989) and muscle tissue (Burke, 2003), and there have been three studies of creatine supplementation in vegetarians that have measured strength or muscle size outcomes:
In a 1997 Belgium study of vegetarians, creatine supplementation did not improve power output (Clarys, 1997).
In a 2000 Swedish study, vegetarians and meat-eaters took 7 g of creatine three times a day for six days. The vegetarians and meat-eaters improved their average power output after creatine supplementation, but only the meat-eaters significantly increased their peak power output (Shomrat, 2000).
A 2003 study from Canada was conducted on 19 vegetarians (including 3 vegans) and 30 non-vegetarians. Participants had been recreational athletes, all with some resistance training but not a lot (Burke, 2003).
For the 7 day loading phase, subjects were given 0.25 g of creatine per kg of lean tissue mass (average of 16.8 g per day). For the 49 day maintenance phase, they were given 0.0625 g per kg of lean tissue mass (average of 4.2 g per day). They were put through an intense weight training routine, focused mostly on the upper body.
Subjects on creatine increased muscle mass more than those receiving placebo, with the vegetarians on creatine increasing most of all (2.4 kg of lean tissue vs. 1.9 kg for non-vegetarians using creatine). The maximum bench press amount increased 15.9 kg for those taking creatine and only 8.7 kg for those taking a placebo. Maximum leg press increases did not vary between the supplementation or diet groups.
Vegetarians on creatine most greatly improved their ability to do work on a knee flexion/extension machine than other groups. Vegetarians had greater increases in muscle concentrations of total creatine and phosphocreatine. Supplemented groups had much higher training volumes. ATP concentrations did not vary among groups.
Based on these three studies, it seems reasonable to conclude that vegetarian weightlifters can improve performance by taking creatine.
The loading phase for vegetarians and non-vegetarians is probably similar, because their dietary intake is negligible compared to the amounts supplemented. However, because the average meat-eater consumes 1-2 g of creatine a day, 30 percent of which is destroyed by cooking (Harris, 2002), the maintenance phase for vegetarians may need to be as high as 3.4 g/day.
Consuming powdered creatine with a sugar solution, such as a sports drink or fruit juice, increases the rate at which muscles absorb the creatine (Casey, 2000).
Supplement companies say that creatine supplements are made without using animal derivatives (Larson, 2002).
Safety of Creatine
In the short term, creatine supplementation does not appear to cause problems in people without a history of kidney problems. One study looked at markers of liver and kidney function after five days of 20 g/day and found no problems; similar studies have confirmed these results (Casey, 2000). No side effects have been found in studies of people taking 20 g/day for up to five weeks; there are some anecdotal reports of muscle cramps and tears from creatine supplementation (Stone, 1999).
The long-term effects of creatine supplementation have not been studied, but there have been no reports of long-term problems. British weightlifters have used creatine for three to five years without problems.
There is one case of a person with a history of kidney disease whose kidney function further deteriorated after taking creatine. Thus, people with kidney disease are warned against taking the supplement (Shomrat, 2000).
While it is not clear that vegan weightlifters must use creatine to achieve maximum results, it appears to be safe in the amounts that have been studied, and it could possibly improve performance.
Carnitine (also known as L-carnitine and acetyl-L-carnitine) is an amino acid that is made in the liver and kidneys. It is also found in meat and dairy products (Chen, 1998), but there is very little found in plant foods. Carnitine is needed for the burning of most fats. Thus, carnitine supplements are promoted by supplement companies for weight loss. However, evidence shows that most people (among the non-vegetarian population) who take the supplements do not lose weight (Villani, 2000). Effects of carnitine supplementation on weightlifting or bodybuilding have not been studied.
Carnitine levels tend to be lower in people eating lower fat, higher carbohydrate diets (Lombard, 1989). When intake of carnitine is low, less carnitine is excreted. Vegans and lacto-ovo vegetarians have lower blood levels of carnitine (Delanghe, 1989; Lombard, 1989; Krajcovicova-Kudlackova, 2000; Stephens, 2011). Researchers in one study didn’t think the lower carnitine levels of vegetarians were unhealthy (Lombard, 1989). It’s not known if the lower levels have any bearing on athletic performance.
Stephens et al. (2011) found that vegetarians’ muscles had a lower ability to absorb carnitine than omnivores. Vegetarians also excreted less carnitine than omnivores, indicating that other tissues or muscles that were not tested were possibly absorbing the carnitine.
Non-vegetarians typically eat 100-300 mg of carnitine per day (Siebrecht, 2000). It would appear safe, therefore, for vegans to take 100-300 mg/day if they choose to do so. In one study, supplementing with 120 mg/day for two months did not significantly increase plasma carnitine levels in 11 vegans, while urinary carnitine excretion did increase (Rebouche, 1993). This implies that the subjects were urinating most of the extra carnitine out, though it is possible that they were utilizing some of it.
There are side effects to large amounts of carnitine. In one study, 2,000 mg of carnitine, twice daily, was associated with nausea and diarrhea in 5 of 18 people (Villani, 2000).
Solgar’s carnitine supplement is made through yeast fermentation of beet sugar (Solgar, 2002).
Carnosine and beta-Alanine
Last updated January 2023
Burke DG, Chilibeck PD, Parise G, Candow DG, Mahoney D, Tarnopolsky M. Effect of creatine and weight training on muscle creatine and performance in vegetarians. Med Sci Sports Exerc. 2003 Nov;35(11):1946-55.
Chen W, Huang YC, Shultz TD, Mitchell ME. Urinary, plasma, and erythrocyte carnitine concentrations during transition to a lactoovovegetarian diet with vitamin B-6 depletion and repletion in young adult women. Am J Clin Nutr. 1998 Feb;67(2):221-30.
Conrado de Souza A, da Silva Brandão M, Lima Oliveira D, Garcez de Carvalho F, Costa ML, Aragão-Santos JC, Santos do Nascimento MV, Silva-Grigoletto M, Mendes-Netto RS. Active vegetarians show better lower limb strength and power than active omnivores. Int J Sports Med. 2022 Jan 27.
Doi T, Matsuo T, Sugawara M, Matsumoto K, Minehira K, Hamada K, Okamura K, Suzuki M. New approach for weight reduction by a combination of diet, light resistance exercise and the timing of ingesting a protein supplement. Asia Pacific journal of clinical nutrition. 2001;10(3):226-32.
Hevia-Larraín V, Gualano B, Longobardi I, Gil S, Fernandes AL, Costa LAR, Pereira RMR, Artioli GG, Phillips SM, Roschel H. High-Protein Plant-Based Diet Versus a Protein-Matched Omnivorous Diet to Support Resistance Training Adaptations: A Comparison Between Habitual Vegans and Omnivores. Sports Med. 2021 Jun;51(6):1317-1330.
Larson E. Vegetarian diet for exercise and athletic training and performing: an update. Vegetarian Nutrition. Vegetarian Dietetic Practice Group of the American Dietetic Association. http://www.andrews.edu/NUFS/vegathletes.htm Accessed November 5, 2002.
Monteyne AJ, Coelho MO, Murton AJ, Abdelrahman DR, Blackwell JR, Koscien CP, Knapp KM, Fulford J, Finnigan TJ, Dirks ML, Stephens FB, Wall BT. Vegan and omnivorous high protein diets support comparable daily myofibrillar protein synthesis rates and skeletal muscle hypertrophy in young adults. J Nutr. 2023 Feb 21:S0022-3166(23)12680-0.
Morton RW, Murphy KT, McKellar SR, Schoenfeld BJ, Henselmans M, Helms E, Aragon AA, Devries MC, Banfield L, Krieger JW, Phillips SM. 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. Br J Sports Med. 2018 Mar;52(6):376-384.
Rodriguez NR, DiMarco NM, Langley S; American Dietetic Association; Dietitians of Canada; American College of Sports Medicine: Nutrition and Athletic Performance. Position of the American Dietetic Association, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and athletic performance. J Am Diet Assoc. 2009 Mar;109(3):509-27.
Ross JK, Pusateri DJ, Shultz TD. Dietary and hormonal evaluation of men at different risks for prostate cancer: fiber intake, excretion, and composition, with in vitro evidence for an association between steroid hormones and specific fiber components. Am J Clin Nutr. 1990 Mar;51(3):365-70.
Stone MH, Sanborn K, Smith LL, O’Bryant HS, Hoke T, Utter AC, Johnson RL, Boros R, Hruby J, Pierce KC, Stone ME, Garner B. Effects of in-season (5 weeks) creatine and pyruvate supplementation on anaerobic performance and body composition in American football players. Int J Sport Nutr. 1999 Jun;9(2):146-65.
Thomas DT, Erdman KA, Burke LM. Position of the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and Athletic Performance. J Acad Nutr Diet 2016;116:501-528.
Thomas EL, Frost G, Barnard ML, Bryant DJ, Taylor-Robinson SD, Simbrunner J, Coutts GA, Burl M, Bloom SR, Sales KD, Bell JD. An in vivo 13C magnetic resonance spectroscopic study of the relationship between diet and adipose tissue composition. Lipids. 1996 Feb;31(2):145-51.
Villani RG, Gannon J, Self M, Rich PA. L-Carnitine supplementation combined with aerobic training does not promote weight loss in moderately obese women. Int J Sport Nutr Exerc Metab. 2000 Jun;10(2):199-207.