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Vegetarian diet for triathletes

The vegetarian triathlete: what to eat if you are meat-free

Whether you’re thinking about going vegan/vegetarian or are already, Nigel Mitchell explains how to get the most from your meat-free diet…

Credit: Alex Tihonov / Moment / Getty Images

The types of foods we choose to eat depend on many factors, such as availability, nutritional requirements, cost, personal tastes, culture, religion and ethical reasons. And one of the most popular ‘diets’, which ticks many of the aforementioned boxes, is vegan or vegetarian. But as triathletes, we need to ask ourselves what the main considerations are when considering such a diet…

First of all, what’s the difference between the two? The main distinction between a vegan and vegetarian diet is that a vegan won’t consume any food that is directly or indirectly produced from an animal. So that means avoiding all meat, fish, eggs, dairy and even foods such as honey. A vegetarian, on the other hand, will not eat the flesh of an animal (some people consider themselves vegetarian but will still eat chicken and fish), but most will include dairy and eggs.

Choosing to become vegan or vegetarian is usually an ethical or moral choice, but many choose it for health reasons. From a sporting perspective, however, let’s examine the nutritional implications for the vegan/vegetarian triathlete.

Vegetarian fuelling for an Ironman


One of the main issues for a vegan/vegetarian athlete is consuming enough quality protein. Proteins are made of amino acids, which are essentially nature’s building blocks – if we think of the protein as a brick wall then the individual bricks are the amino acids.

There are 22 amino acids in total, of which eight are considered essential. So in order to meet our protein needs we must eat proteins that provide all of the essential amino acids. For a vegetarian, this can easily be achieved by consuming dairy foods and eggs. Of course there are plenty of other non-animal foods that are also good sources of protein, but they’re often lacking in one or more essential amino acids (head to 220tri.com for a table of foods containing approximately 10g of non-meat and vegetable protein). So I recommend mixing the proteins, e.g. beans and pulses, and planning your meals more carefully in advance.


One of the reasons why some choose vegan and vegetarian diets is because they tend to be lower in fat, but another consideration is the type of fats on offer with vegan/vegetarian diets. The English diet tends to be low in the omega-3 fats, and we know fish oil supplements are very popular to help boost healthy levels. But seeds and nuts are also a great vegetarian- and vegan-friendly way of providing these essential dietary fats. Flaxseed in particular provides great fats, but remember to ‘mill’ them or they pass straight through.


Iron, and in particular a form of iron that’s easily absorbed and used by the body, is often challenging for the vegan/vegetarian athlete to obtain. And athletes in particular require more iron because during heavy training the body is stressed and produces hepcidin, a hormone that reduces our iron absorption.

If you’re a vegan/vegetarian triathlete it’s worth having a blood test to check your ferritin levels (effectively your iron stores). Your green leafy vegetables, such as spinach, and your pulses, nuts and seeds are all good iron providers, but including vitamin-rich foods, such as tomatoes and oranges, to eat alongside them helps improve iron absorption. Also avoid strong tea with meals because the tannins reduce iron absorption.


There are some great soya-based protein supplements on the market (check out www.otesports.co.uk), and if you want to use an iron supplement then Healthspan Elite’s (www.healthspan.co.uk/elite) or Spatone’s (www.nelsonsnaturalworld.com) offerings are easy on the stomach. Other supplements to consider for a vegan and vegetarian diet are creatine and beta-alanine, and it may be worth considering taking a small maintenance dose of 2g and 1g, respectively.

If you’re considering switching to a vegan/vegetarian diet, don’t worry that your health and performance will suffer as a result. As I’ve highlighted here, there’s no need for a vegan/vegetarian athlete to be disadvantaged over a carnivorous one. One of the growing trends at the moment is for people to go one or two days a week without eating meat, which could be an ideal compromise if the thought of giving up a Sunday roast or occasional bacon sandwich treat is too much. Whatever you choose to do the main thing is to make an informed choice and to make sure you enjoy the food you eat.

5 of the best sources for protein and iron

1 Quinoa

This is a great source of protein, fats and Vitamin B vitamins

2 Pistachio nuts

High in protein and antioxidants, with a very low glycemic index

3 Mixed pulses

Provide a good range of amino acids and one of the better vegetarian providers of iron

4 Mixed seeds, including flax

Good range of healthy fats, especially omega-3, protein and iron

5 Soya milk

Good protein supply, fortified with calcium and decent iron provider


Nutrition myths busted!

Profile image of Nigel Mitchell Nigel Mitchell Sports nutritionist and author


Sports nutritionist Nigel Mitchel is the nutritional consultant to British Athletics and British Sailing. Prior to this he was the GB Cycling Team and Team Sky's head of nutrition. He's the author of The Cyclist’s Cookbook, The Plant-Based Cyclist and Fuelling the Cycling Revolution: The Nutritional Strategies and Recipes Behind Grand Tour Wins and Olympic Gold Medals.