Every day, millions of health-conscious individuals swallow a small capsule or soft gel with the faith that it’s protecting their cells, shielding their heart, or slowing the hands of time. It’s a routine built on decades of marketing and a basic belief:
more antioxidants = better health.
But what if one of the most common antioxidants found in supplements – touted for everything from cardiovascular support to skin rejuvenation – could actually be doing more harm than good for certain people?
This isn’t pseudoscience. It's not a fringe theory. This is real science, backed by growing evidence from clinical studies and genetic research.
And what’s more chilling?
Your genes may be silently turning this “healthy” nutrient into a toxic threat.
Let’s talk about oxidative stress – the cellular equivalent of rust. It’s long been the villain in the ageing process, associated with everything from cancer to heart disease. Naturally, antioxidants stepped in as the hero: quenching free radicals and offering cellular salvation.
But recent studies have shown that excessive supplementation with one antioxidant in particular has been associated with an increased risk of cancer in certain individuals.
Even more troubling: this risk isn’t evenly distributed. It depends on something personal, something hidden deep within your biology – your DNA.
Genetics: The Game-Changer in Supplement Safety
Thanks to advances in genetic testing, scientists have uncovered a disturbing truth: certain variants in genes like TTPA, APOE, GSTP1 and CYP4F2 can influence how your body handles this antioxidant.
In people with these variants, supplementation can lead to:
· Accumulation in tissues, particularly the liver and brain
· Increased oxidative damage instead of protection
· Greater risk of haemorrhagic stroke
· Elevated cancer risk (notably prostate cancer, in some studies)
All from a supplement that was supposed to reduce these very risks.
The Antioxidant in Question: Vitamin E
Vitamin E, often seen as the golden child of skin creams and heart health supplements, is not as universally safe as once believed. While it plays a critical role in protecting cell membranes, its supplementation – especially in high doses or synthetic forms – is now under serious scrutiny.
Here's what the research says:
· High-dose vitamin E (≥400 IU/day) has been linked to increased all-cause mortality in some meta-analyses.
· The SELECT trial, a major study looking at vitamin E and prostate cancer risk, found a 17% increase in prostate cancer among men taking vitamin E supplements.
· People with certain APOE4 genotypes (also associated with Alzheimer's risk) may respond poorly to vitamin E supplementation due to altered lipid transport and antioxidant dynamics.
GSTP1 for example has some frightening effects - In individuals with lower GSTP1 activity:
· Vitamin E can build up into pro-oxidant forms, especially in the presence of environmental stressors or inflammation.
· Instead of neutralising free radicals, excess vitamin E may contribute to oxidative stress — the very thing it's meant to prevent.
· This oxidative imbalance has been linked to higher cancer risk, including prostate, breast, and lung cancers.
For example, studies have shown that men with the GSTP1 Val allele who supplemented with vitamin E had a higher risk of aggressive prostate cancer compared to those without the variant. It’s a powerful example of how genetic susceptibility can completely flip the expected outcome of a supplement.
Should You Stop Taking Vitamin E?
Not necessarily — but you should stop taking it blindly.
The truth is, vitamin E is essential. But the dose, form, and especially your genetics matter more than you think. While food sources of vitamin E (nuts, seeds, leafy greens) are generally safe and beneficial, the same cannot be said for megadose in supplement form.
