High intake of whole grains, fiber, fish and omega-3 fatty acids linked to lower risk of death in adults with type 2 diabetes

Eating a diet high in whole grains, fibre, fish and n-3 polyunsaturated fatty acids (PUFAs) may reduce the risk of dying from all causes in adults with type 2 diabetes (T2D), according to a systematic review and meta-analysis synthesising all the available evidence, presented at this year's European Association for the Study of Diabetes (EASD) Annual Meeting.

To find out more, German researchers did a systematic review of 107 prospective observational studies investigating any dietary factors and the risk of death from all causes in adults with T2D, up to June 2022.

The analyses found that there was moderate-certainty of evidence of a protective association between the intake of whole grain, fibre, fish, n-3 PUFAs and death from all causes. Adding one serving (20 g/day) of whole grain from foods such as brown bread and rice or breakfast cereals was associated with about a 16% reduction. Each serving per week increase in fish consumption was associated with a 5% lower risk of death.

Similarly, an additional 5 g per day intake of dietary fibre and 0.1 g per day increase in n-3 PUFAs was associated with a reduced risk of death from all causes—14% and 13% lower, respectively. The body does not produce n-3 fatty acids naturally, so good sources include fish, vegetable oil, nuts (especially walnuts), flax seeds and flaxseed oil, and leafy vegetables.

Evidence of lower certainty also suggests that eating large amounts of vegetables and plant protein may be beneficial. A daily increase of 100 g of vegetables and 10 g of plant proteins such as nuts, tofu, beans, lentils and peas was associated with a 12% and 9% lower risk of death, respectively.

Possible beneficial effects of these foods include their link with favourable changes in blood pressure, cholesterol, blood sugar levels and anti-inflammatory effects, which might help to lower the risk of comorbidities such as cardiovascular diseases and cancer.