Why Do Some People React Badly To A Vegan Diet?

The suitability of a vegan diet is a pretty contentious topic and one which frequently brings out keyboard warriors.

Many of us will have friends or family whose health has deteriorated when they’ve cut out meat, and the only way to restore it was to return to an omnivorous diet.

So what are the reasons why some people react badly to a vegan diet? Let’s take a look.

Lack Of Heme Iron

While you can source iron from plant foods such as broccoli, wholemeal bread and nuts, there’s a particular type of iron which is exclusively found in animal products.

It’s called heme iron, and our bodies are much better at absorbing it than non-heme iron found in plants.

Iron deficiencies can cause a loss of energy and headaches, so this could be a reason for some people reporting they feel unwell on a vegan diet.

Lack Of Vitamin A

Vitamin A, sometimes known as retinol, helps support the immune system.

While it’s commonly believed that the vitamin can be found in plants, the true form is only sourced from animal products like milk, cheese, oily fish and eggs.

Plants only contain vitamin A precursors which the intestine and liver then convert into retinol.

Vitamin B12 & Vitamin D Deficiencies

Vitamin B12 is frequently held up as one of the most convincing arguments against veganism.

It can only be sourced from animal products and contributes to the healthy functioning of red blood cells.

Adults need about 1.5 micrograms of vitamin B12 a day in order to stay healthy. 

While vegans can supplement their vitamin B12 intake, if this is insufficiently planned or their body doesn’t absorb it properly, it could lead to health problems.

This is similar to the case of vitamin D, which as well as being sourced through sunlight, is obtained through dairy products.

Vitamin D helps regulate the body’s calcium levels which helps keep teeth, bones and muscles healthy.

While it can be sourced through green leafy vegetables, if this is improperly planned then a deficiency can occur.