How Diets May Help Prevent Diseases in Later Life
Adopting a Mediterranean or plant-forward diet may help prevent age-related diseases like dementia, heart disease, and diabetes. Recent studies show that nutrient-rich foods can reduce inflammation, support brain health, and improve longevity even in people with genetic risk factors.
EXPERT NUTRITION TIPS
5/22/20253 min read
How Diets May Help Prevent Diseases in Later Life
Aging is inevitable. But how it unfolds — sharp and active into our eighties or weighed down by illness decades earlier — depends on more than luck. Yes, genes matter, but science keeps pointing to another powerful influence: the food we eat every day.
In recent years, researchers — particularly in the UK — have uncovered striking links between diet and the prevention of diseases that often come with age. The message is hopeful: while we can’t rewrite our DNA, we can make choices at the dinner table that tilt the odds in our favor.
The Mediterranean Diet and Dementia
One of the strongest examples comes from a 2023 study in BMC Medicine. Scientists followed more than 60,000 people in the UK Biobank for nine years. Those who stuck closest to a Mediterranean-style diet — heavy on vegetables, fruit, legumes, whole grains, nuts, olive oil, and fish — had a 23% lower risk of developing dementia compared with those who didn’t.
The most remarkable part? The benefit was just as strong in people genetically at higher risk of Alzheimer’s disease (Shannon et al., 2023, BMC Medicine).
More recently, a 2025 paper in Nature Medicine confirmed that this way of eating seems protective even for carriers of the APOE4 gene, the most powerful known genetic risk factor for Alzheimer’s. Harvard researchers highlighted similar findings, suggesting diet could partly offset inherited vulnerability (Harvard Gazette, 2025).
In plain terms: your DNA may set the stage, but your diet helps decide how the play unfolds.
Why Food Protects the Brain
Why does food play such a big role in memory and thinking? The answer lies in inflammation and circulation. Diets rich in plants supply antioxidants that ease cellular stress, healthy fats that keep blood vessels supple, and fiber that nourishes a healthy gut microbiome. Working together, these nutrients help lower inflammation and boost blood flow to the brain — two major factors in protecting against cognitive decline.
It’s not about a single “superfood” that solves all the problems, but it’s the synergy of many foods working together, day after day.
Beyond Dementia: Other Age-Related Diseases
Brain health is only part of the picture. The way we eat also affects other conditions that often appear with age:
Heart disease. The landmark PREDIMED trial showed that following a Mediterranean diet can lower the risk of major cardiovascular events by about 30% (Estruch et al., 2013, NEJM).
Type 2 diabetes. A 2019 meta-analysis in PLOS Medicine found that plant-based diets were strongly linked to a lower risk of diabetes. Whole grains, beans, and vegetables improve insulin sensitivity and help keep blood sugar steady.
Cancer. Research has connected plant-rich eating patterns with reduced cancer risk, including prostate cancer. Men who adopted vegetarian or plant-focused diets experienced meaningful reductions (Orlich et al., 2016, Journal of Urology).
The common thread? Diets centered on whole, plant-forward foods deliver nutrients that protect cells, regulate metabolism, and curb the chronic inflammation that drives disease.
Practical Steps for Healthy Aging
You don’t need to overhaul your diet overnight. Small shifts make a difference:
Go Mediterranean-ish. Build meals around vegetables, beans, nuts, fruit, and olive oil.
Mix your proteins. Rice and beans, hummus and pita, or tofu with grains — all create complete proteins without relying heavily on meat.
Spice it up. Spices like turmeric, cumin, paprika, and garlic don’t just boost flavor, they also deliver anti-inflammatory benefits.
Think long-term. Consistency beats intensity. It’s what you do most days, not just during a “health kick,” that matters.
Looking Beyond
No single diet guarantees disease-free aging. But the evidence is clear: food choices shape how we age just as much as — if not more than — our genetic lottery.
British and international studies point in the same direction: nutrient-dense, plant-forward diets like the Mediterranean pattern don’t just help with weight and heart health. They may also protect the brain from dementia and improve the odds of living not only longer, but better.
The takeaway? Every meal is a chance to invest in your future self — one that’s active, independent, and full of vitality well into later life.
References
Shannon, O.M. et al. (2023). Mediterranean diet, dementia risk and genetic susceptibility in the UK Biobank. BMC Medicine.
Nature Medicine (2025). Mediterranean diet and dementia risk reduction study.
Harvard Gazette (2025). Mediterranean diet offsets genetic risk for dementia.
Estruch, R. et al. (2013). Primary prevention of cardiovascular disease with a Mediterranean diet. NEJM.
Satija, A. et al. (2019). Plant-based diets and diabetes risk: a meta-analysis. PLOS Medicine.
Orlich, M.J. et al. (2016). Vegetarian dietary patterns and prostate cancer. Journal of Urology.
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