Will a vegan diet harm or help your health?

6th December, 2019 • 5 min read

Public interest in vegan diets has grown in recent years. This may be, at least in part, because these diets have become synonymous with health. From bringing about weight loss to preventing cancer, many health claims surround vegan diets.

But what does science say? Are vegan diets the cure-all they appear to be or can they actually harm your health?

What is a vegan diet?

A vegan diet is entirely plant-based. This means that you don’t eat animal products such as honey, eggs, gelatin, dairy or meat. As plant-based foods are low in saturated fat and provide plenty of vitamins and minerals, you can get all the nutrients you need from a vegan diet.

However, eating no animal products can carry health risks if you don’t plan your diet properly. To do so, you’ll first need to understand the nutrients you can miss out on by removing animal products from your diet, and how to replace them with plant-based products.

Risks of a vegan diet

When following a vegan diet, there are a few vitamins and minerals you can miss out on. These include vitamin B12, iron and calcium. Here’s how to make sure you get enough of these nutrients on a vegan diet.

How to get vitamin B12 on a vegan diet

Vitamin B12 is needed to keep your blood supply and nervous system healthy, but it’s only found naturally in foods from animal sources. That’s why if you decide to follow a vegan diet, you should take a vitamin B12 supplement. Ideally, adults should have 1.5mcg of vitamin B12 a day, but speak to a doctor to find out how much vitamin B12 you should take to meet your daily needs.

It’s possible to get vitamin B12 from plant-based foods that have been fortified with the nutrient. These include:

  • breakfast cereals fortified with B12
  • unsweetened soya drinks fortified with vitamin B12
  • yeast extract such as Marmite, which is fortified with vitamin B12

How to get iron on a vegan diet

Iron plays an important role in the development of red blood cells, which carry oxygen around the body. If you don’t get enough iron you can develop

iron-deficiency anaemia
. This is more common in adults who are pregnant or have heavy periods.

A well-planned vegan diet can provide plenty of iron, although iron found in plants is not absorbed as well as the iron found in meat. Plant-based sources of iron include:

  • pulses
  • wholemeal bread and flour
  • breakfast cereals fortified with iron
  • green leafy vegetables such as watercress, broccoli and spring greens
  • nuts and dried fruits such as apricots, prunes and figs

Speak to a doctor if you’re concerned about getting enough iron.

How to get calcium on a vegan diet

Calcium is important for keeping your teeth and bones healthy. If you don’t get enough calcium as an adult, you could increase your risk of

and rickets (

There are plenty of non-dairy sources of calcium, including:

  • tofu
  • green leafy vegetables
  • nuts
  • soya beans
  • fortified plant-based milk
  • bread

Take care to read food labels to make sure you’re getting enough calcium.

Find more information on how to

get the right nutrients from a vegan diet

The health benefits of a vegan diet

Have you heard lots of claims about what a vegan diet can and can’t do for your health? Test your knowledge of the facts about vegan diets with this quick quiz.

Switching to a vegan diet causes weight loss. True or false?


While cutting out animal products can lead to weight loss, it’s not a guaranteed outcome. The only way to lose weight is to focus on creating a calorie deficit, where you burn more calories than you consume. A vegan diet can help you do this because plant-based foods contain a lot of fibre, which keeps you fuller for longer.

A vegan diet may help to prevent type 2 diabetes. True or false?


Research has found that people who eat a vegan diet have a 23% reduced risk of developing type 2 diabetes. However, the research also found that those who ate a plant-based diet centred on fruits, vegetables and wholegrains had an even lower risk. But this doesn’t mean that a vegan diet is inherently healthy; there are many processed vegan foods that are high in saturated fat and sugar.

More research needs to be done to rule out other factors that could influence the results, such as weight.

A vegan diet can cure cancer. True or false?


There is no conclusive evidence that a vegan diet can cure cancer. However, there is some evidence to suggest a plant-based diet can help prevent some cancers. Many studies have found that fruit, vegetables, wholegrains and other plant-based foods may protect against cancer.

Can you get the benefits of a vegan diet without going vegan?

Most people can benefit from cutting down on the amount of meat in their diet. There’s no magic percentage of animal products versus plant foods you should eat to get the most benefits. It will vary from person to person. Instead, focus on adding more wholegrains and plant-based foods into your diet.

Always speak to a doctor before making any big changes to your diet.

Important: Our website provides useful information but is not a substitute for medical advice. You should always seek the advice of your doctor when making decisions about your health.