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Vegan diets are turning heads in the boxing world…. But do they actually work? 


Some high-profile boxers such as Timothy Bradley Jr. and David Haye have tried Vegan diets in the past as a way to improve their body composition, health and performance.

With more following suit and going plant-based, Boxing Science investigates whether a vegan diet really help boxing performance?

As with many types of training or diets, there are advantages and disadvantages. As sport scientists we have to weigh up the options and select the most appropriate method to optimise physical performance.

What are vegan diets?

A vegan diet consists of plant-based foods but omits meat, fish, dairy and eggs.

Many people who eat a vegan diet choose to do so because of health reasons or because they’d like to be more conscious of earths resources, ethical issues surrounding animal care as well as health benefits of a plant-based diet.

What are the benefits?

Vegan diets are usually high in fibre, magnesium, folic acid, vitamin C and E and phytochemicals whilst lower in saturated fat. This means that a vegan diet is nutrient dense.

Vegan diets tend to be linked with lower risks of cardiovascular disease because of the increased nutrient density compared to a “typical” normal diet. However, most scientific studies only compare diets based on health markers not sports performance.

What are the disadvantages?

Vegan diets are typically deficient in saturated fat which is important for hormone production and are often at risk of vitamin D and zinc deficiency.

Saturated fat: Important for hormone production. 

Omega 3: Improves joint health. 

Vitamin D and Zinc: Improves the function of the immune system. 

Calcium: Improves bone health.

Vegans are at risk of being deficient in vitamin B12, an important vitamin that is only available from animal products. Vitamin B12 is important for DNA synthesis, fatty acid and amino acid metabolism, functioning of the nervous system, particularly myelin synthesis, and is important in the development of red blood cells in bone marrow.

In addition, Vegan diets if not planned appropriately can be low in calcium because of the omission of dairy products.  Without calcium-fortified foods, Vegans can be at a high risk of suffering bone fractures, especially when coupled with a low energy intake.

Can I still get enough protein?

Yes, but it’s difficult. Vegan diet studies on weight management have only investigated weight loss not fat mass and fat-free mass.

An insufficient vegan diet is likely to increase the risk of losing lean tissue due to the low consumption of protein, the recommended daily intake of protein is around 0.8 grams of protein per kilogram of body mass (g/kg). A 70 kg individual therefore needs at least 56 g of high biological value protein per day to maintain protein synthesis.

A highly active boxer will demand a higher protein intake (1.6-2g/kg) to increase recovery and aid training adaptation as well as aid fat mass loss. Having adequate quantities and high quality sources of protein is very important for boxers and combat athletes and is a major challenge on vegan diets.

Below is a chart of protein bioavailability which shows that animal protein sources are more easily absorbed compared to non-animal sources. Plant based foods have a lower leucine content compared to animal products which helps increase protein synthesis to a greater extent than the other amino acids.

Supplements might be needed to ensure boxers have enough protein intake, this can become very expensive as well as potentially dangerous if the products are not batch tested for banned substances.

So how will a vegan diet affect my performance?

Boxing requires high levels of different types of physical fitness including aerobic and anaerobic endurance, strength and speed. A vegan diet will be able to fuel performance in aerobic and anaerobic endurance due to the high carbohydrate content of the diet, however the protein content might limit repair and formation of muscle tissue, potentially leading to impaired strength adaptations and muscle mass.

This is likely to have a negative effect on your physical performance.


However, it is possible to have success using a vegan diet as long as you plan your diet well. Below are examples of vegan friendly food sources that will help you make good choices on this type of diet.

The table above is from our friend and colleague Dr Dave Rogerson’s paper “Vegan diets: Practical advice for athletes and exercisers”.

The main concern regarding vegan diets for athletes arises from inadequate protein intake, below is a table of high-protein foods that are suitable for vegans. In in this manuscript Dr Rogerson also outlines a typical diet for a vegan athlete which can be adapted to suit your own requirements.


There is no evidence that a vegan diet can benefit performance over a normal, balanced sports nutrition plan.

Therefore athletes should not choose to be ‘plant-based’ in order to boost performance, however they can still become Vegan if it’s a personal choice.

There are limitations to a vegan diet for athletes however with the correct food choices it is possible to alleviate these concerns.

At Boxing Science we encourage athletes to eat a wide variety of foods, including 5 to 9 portions of fresh fruit and vegetables per day alongside clean unprocessed lean meats, fish, dairy and starches. There is no reason why athletes cannot also include some vegan friendly foods such as nuts, legumes, soy and seaweeds/algae to help contribute to a well-rounded diet.

This is more likely to improve your training and performance compared to a single diet alone, as well aid your recovery in between training sessions and help you to increase/maintain lean muscle mass.