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Eating A More Varied Diet Linked To Lower Diabetes Risk In Korean Adults

Over 16,000 Korean adults with more varied diets had a lower rate of new type 2 diabetes over nearly 100,000 person-years.

By Dr. Axe Editorial Team · October 15, 2026 · 1 source · Watch

A study published October 15, 2026 in the British Journal of Nutrition found that Korean adults eating a more varied diet had a lower rate of new type 2 diabetes, with each step up in overall dietary diversity linked to a 44% lower rate in men and a 27% lower rate in women.

16,666adults tracked

44%lower risk, men

27%lower risk, women

953new cases

Researchers followed 16,666 Korean adults age 40 and older who did not have type 2 diabetes at the start, tracking them for a combined 96,609 person-years using repeated food frequency questionnaires at each visit. Over that period, 953 people developed type 2 diabetes. The researchers found a significant inverse linear trend: as overall dietary diversity scores rose, type 2 diabetes rates dropped, with an incidence rate ratio of 0.56 in men (a 44% lower rate) and 0.73 in women (a 27% lower rate). Looking at specific food groups using a highest-versus-lowest quarter comparison, greater variety within milk and dairy products was linked to lower diabetes rates in both men and women, greater fruit variety was linked to lower rates in men, and greater variety among vegetables, seaweed and mushrooms was linked to lower rates in women. No meaningful sex-related differences were found in how these patterns played out.

The authors state that higher overall dietary diversity, and greater variety specifically in non-energy-dense groups like fruits, vegetables and dairy, was associated with lower type 2 diabetes risk, and suggest that maintaining this kind of diversity may help prevent the disease. As general nutritional background, eating a wider range of foods naturally brings a broader mix of fiber, vitamins, minerals and plant compounds, which can support healthier blood sugar regulation compared with repeating the same few foods.

Type 2 Diabetes Rate Linked to Higher Dietary Diversity

British Journal of Nutrition, 2026, Kim et al.

This is an observational study using self-reported food questionnaires, so it shows a link between dietary variety and diabetes risk, not proof that diversity itself causes the lower rates. Person-years were tracked over the study period as reported; an average follow-up duration was not given. Funding and conflicts were not reported in the abstract.

Dr. Axe’s Take

This tracks with what I see as the deeper issue in the modern diet: it's not just too much sugar, it's too narrow. Most people rotate through the same 10 or 15 foods weekly, starving the gut microbiome of the variety it needs to produce short-chain fatty acids that help regulate blood sugar. My advice: build one meal this week around a food group you rarely eat, whether that's a new vegetable, fermented dairy like plain kefir or yogurt, or a different fruit. Aim for color and category variety, not just avoiding sugar, paired with fiber-rich whole foods.

— Dr. Axe

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Study summary

Who: 16,666 Korean adults, age 40+, without type 2 diabetes at baseline
Design: Prospective cohort study (Korean Genome and Epidemiology Study), repeated food frequency questionnaires
Dose: Not applicable; dietary diversity scores from repeated FFQ at each visit
Primary result: Each step up in overall dietary diversity linked to 44% lower T2D rate in men, 27% lower in women (IRR 0.56 and 0.73), over 96,609 person-years
Secondary: Highest vs lowest quarter: higher dairy diversity linked to lower risk in both sexes; higher fruit diversity linked to lower risk in men; higher vegetable/seaweed/mushroom diversity linked to lower risk in women; 953 total T2D cases
Funding / conflicts: Funding and conflicts not reported in the abstract.
Date: Oct 15, 2026