March 2, 2024

I, Science

The science magazine of Imperial College

A recent study suggests the beginnings of Alzheimer’s disease may relate to the levels of vitamin A received in the womb.

A recent study suggests the beginnings of Alzheimer’s disease might stretch back as far as the womb. The new research, carried out at the University of British Columbia and the Children’s Hospital of Chongqing Medical University, investigated how vitamin A deficiency in pregnant mothers and new-borns, might be linked to Alzheimer’s.

Alzheimer’s is a disease marked by memory loss and cognitive decline. While no one knows what causes Alzheimer’s, it is associated with certain changes in the brain, like protein-clumping.

Vitamin A is a nutrient in fruits, vegetables, eggs, fish, and dairy, and is important in early brain development. Vitamin A deficiency is widespread in the developing world. However, vitamin A supplements have to be taken with caution, as excessive vitamin A has been linked to birth defects and bone fractures in the elderly.

This study was picked up by newspapers who claimed “eating your five-a-day” (The Telegraph) or “fruit and vegetables when pregnant” (The Daily Mail) staves off Alzheimer’s.

“Our study clearly shows that marginal deficiency of vitamin A, even as early as in pregnancy, has a detrimental effect on brain development and has long-lasting effects that may facilitate Alzheimer’s disease in later life,” said Dr. Weihong Song, the paper’s principle investigator.

But does it?

Previous studies have linked Alzheimer’s to low vitamin A, albeit in elderly patients. To their credit, the researchers looked at 330 elderly people in China and found some link between poor cognitive test scores and vitamin A deficiency. However, poor scores does not necessarily mean these people had Alzheimer’s, nor is the vitamin-cognition relationship necessarily cause-and-effect. We should also be wary of applying this data to more affluent regions like the UK, where vitamin A deficiency is not nearly as widespread.

However, the focus of their paper was vitamin A deficiency in mothers and its effects on their children. To investigate this, the researchers used genetically-engineered mice to develop Alzheimer’s. These mice and their offspring were fed different combinations of normal, or vitamin A-deficient diets.

Some evidence was found suggesting vitamin deficiency in mother mice had a small impact on their offspring’s spatial memory. Giving vitamin-deficient mothers vitamin A supplements, helped their offspring perform slightly better, and reduced protein-clumping in the offspring’s brains.

So does a mother’s vitamin A intake determine whether her child will get Alzheimer’s? I would hold off judgement until stronger evidence comes in, and preferably evidence in humans. Although, we can at least agree there is nothing wrong with a balanced diet.

Eugene Kwa is studying Biomedical Science

Banner image: Alzheimers, onephoto