Veganism is one of the fastest-growing millennial trends. In the United States, it grew by 600% between 2014 and 2017.

Recent concern about the nutritional gaps in plant-based diets has led to warnings, such as restricted brain development and irreversible damage to a person's nervou...

One study supplemented Kenyan schoolchildren with three different types of soup (meat, milk and oil) as a snack over seven school terms. 

The children who ate the soup containing meat each day had a significant edge: they outperformed all the other children on a test for non-verbal...

Several essential nutrients are not available from plants or fungi. Creatine, carnosine, taurine, EPA and DHA omega-3, haem iron and vitamins B12 and D3 generally only occur naturally in foods from animal products.

The nutrients found in vegan foods are minimal. To get the minimum am...

Vitamin B12 is only found in animal products like eggs and meat.

Low B12 is widespread in vegans. There are some cases of children whose brains failed to develop because of their vegan parents.

Later in life, the IQ is directly correlated with the amount of B12 in a person's blood. th...

Iron plays a prominent role in brain development and is essential throughout our lives. One study found that giving women iron supplements led to intellectual gains. In those whose blood iron levels improved, their cognitive performance increased between five- and seven-fold.

Some of the essential nutrients can be acquired from supplements. However, nutrients such as taurine are easily overlooked. Others are so obscure that vegans are unlikely to have even heard of them.

• There are small amounts of taurine in some dairy products, but the primary dietary sour...