Eating nuts may slash heart disease risk in diabetics: Study

Eating a handful of tree nuts daily, such as almonds, walnuts and pistachios, may reduce the risk of cardiovascular disease among people with type 2 diabetes, researchers, including one of Indian origin, have found.

According to the study published in the journal Circulation Research, type 2 diabetes is associated with an increased risk for high cholesterol, heart disease and stroke.

Nuts are full of unsaturated fatty acids, phytochemicals, fibre, vitamin E and folate, as well as minerals including calcium, potassium and magnesium, said researchers from the Harvard TH Chan School of Public Health in the US.

However, little is known about the health benefits, if any, that nuts might offer people with type 2 diabetes who face a greater risk for heart health complications, they said.

Researchers used self-reported diet questionnaires from 16,217 men and women before and after they were diagnosed with type 2 diabetes and asked them about their consumption of both peanuts and tree nuts over a period of several years.

During follow-up, there were 3,336 cases of cardiovascular disease (including 2,567 coronary heart disease cases and 789 stroke cases) and 5,682 deaths (including 1,663 deaths from cardiovascular disease and 1,297 deaths from cancer).

"Cardiovascular disease is the leading cause of death and a major cause of heart attacks, strokes and disability for people living with type 2 diabetes," said Prakash Deedwania, a professor at the University of California-San Francisco School of Medicine in the US.

"Efforts to understand the link between the two conditions are important to prevent cardiovascular complications of type 2 diabetes and help people make informed choices about their health," Deedwania said.

The latest findings provide evidence that supports the recommendation of including nuts in healthy dietary patterns for the prevention of cardiovascular disease complications and premature deaths among individuals with diabetes, researchers said.

"Moreover, even when people were in the habit of eating nuts before their diabetes diagnosis, adding more nuts to one's diets proved beneficial probably at any age or stage," said Gang Liu, a researcher at the Harvard TH Chan School.

"It seems never too late to improve diet and lifestyle after diagnosis among individuals with type 2 diabetes," Liu said.

Researchers found that eating all kinds of nuts offered some heart-healthy benefits, with tree nuts showing the strongest association.

The results also showed that eating even a small amount of nuts had an effect.

Compared to people with type 2 diabetes who ate less than a single 28-gramme serving per month, eating five servings of nuts per week had a 17 per cent lower risk of total cardiovascular disease incidence.

They also had a 20 per cent lower risk of coronary heart disease, a 34 per cent lower risk of cardiovascular disease death, and a 31 per cent reduced risk of all-cause mortality.

Compared with people who did not change their nut-eating habits after being diagnosed with diabetes, those who increased their intake of nuts after being diagnosed with diabetes had an 11 per cent lower risk of cardiovascular disease.

They also had a 15 per cent lower risk of coronary heart disease, a 25 per cent lower risk of cardiovascular disease death, and a 27 per cent lower risk of all-cause premature death.

Each additional serving per week of total nuts was associated with a three per cent lower risk of cardiovascular disease and six per cent lower risk of cardiovascular disease death.

Tree nuts such as walnuts, almonds, Brazil nuts, cashews, pistachios, pecans, macadamias, hazelnuts and pine nuts were strongly associated with reduced cardiovascular risk compared with peanuts, with are actually legumes because unlike tree nuts, peanuts grow underground.

While the exact biological mechanisms of nuts on heart health are unclear, researchers noted that nuts appear to improve blood sugar control, blood pressure, metabolism of fats, inflammation and blood vessel wall function.

Researchers explain that tree nuts may offer more benefits because of they contain higher levels of these nutrients than peanuts.