In the news: A Role for Vitamin D in Cataract? Folic Acid + DHA Support Mental Function

Connection Between Vitamin D & Cataract?

It’s too soon to say with certainty whether there is a relationship between blood levels of vitamin D and the formation of cataracts. However, a new analysis suggests that it is a possibility.

Researchers performed a meta-analysis(1) of four existing observational studies involving a total of more than 10,900 participants with cataracts and 10,000 without cataracts who served as controls.

The analyses revealed that blood levels of vitamin D in the cataract group was lower than in the control group, and decreased levels of the vitamin was associated with a higher occurance of cataract.

Digging deeper into the data showed that lower vitamin D levels affected cataract risk in both men and women alike.

Looking at types of cataract, vitamin D levels was tied to the risk for two of the three types of age-related cataract: risk of nuclear cataract (found at the center of the eye and the most common type), and to posterior subcapsular cataract (found on the back of the eye’s lens). It was not associated with cortical cataract.

The development of cataracts is a complex process – a process influenced by genetics and other factors such as exposure to ultra-violet light, air pollution and tobacco smoke.

It is possible that Vitamin D could be involved in lens protection as it plays a role in regulating genes and has antioxidant actions which may help protect against oxidative stress and cellular damage in the lens.

It should also be noted that other studies have shown that vitamin D deficiency may have an adverse impact on ocular and visual health, such as age-related macular degeneration, glaucoma and diabetic retinopathy.

The study authors acknowledge that the vitamin D-cataract connection is not fully understood, and they point to the need for larger scale studies.

In the meantime, it’s a good idea to maintain healthy blood levels of vitamin D since it plays an essential role in preserving overall health.

Folic Acid & DHA Support Cognitive Function

Studies conducted over the past decade or so have implicated folic acid and the omega-3 fatty acid DHA as two important nutrients in helping maintain cognitive function in older aged individuals.

In a new study(2), researchers examined whether both nutrients combined coud improve mental function in those with mild cognitive impairment (MCI). And to understand how these nutrients may be working, they measured biomarkers of oxidative damage of DNA and the health of mitochondria (the energy-producing structures inside cells).

Two hundred and eighty particpants with MCI were randomly assigned to receive daily: folic acid (800 mcg) and DHA (800 mg), folic acid alone, only DHA or placebos.

After 12 months, testing showed that some measures of cognition improved in the single nutrient and combined nutrient groups compared to placebo.

Both nutrients alone or combined also lowered biomarkers of oxidative damage while increasing mitochondrial numbers vs. placebo, suggesting that the nutrients work by lessening the effects of oxidative damage and enhancing mitochondrial activity.

Importantly, the combination of folic acid and DHA was better than either nutrient alone in improving cognition.

Many foods are fortified with folic acid, a B-vitamin also found iwithin multi-vitamin supplements. Eating fatty fish regularly will provide dietary DHA.

References

1. Jue Z, et al. Association between vitamin D level and cataract: A systematic review and meta-analysis Graefes Arch Clin Exp Ophthalmol. Epub Aug. 23, 2024.
2. Mengyue L,i et al. Cognitive benefits of ffolic acid, docosahexaenoic acid, and a combination of both nutrients in mild cognitive impairment: Possible alterations through mitochondrial function and DNA damage. Gerontology 70:940–49, 2024.