Hazelnuts found to improve magnesium and vitamin E levels in older adults

07 Dec 2018 --- Older adults who consumed hazelnuts for a few months significantly improved their levels of two key, underconsumed micronutrients, according to research from Oregon State University. The small-scale study, partly funded by the Hazelnut Marketing Board of Oregon, saw 32 people age 55 and older eat about 57 grams of hazelnuts daily for 16 weeks. This resulted in increased blood concentrations of magnesium and elevated urinary levels of a breakdown product of alpha tocopherol, commonly known as vitamin E.

The findings, published in the Journal of Nutrition, are important because many Americans do not eat adequate amounts of either micronutrient. Older adults are at particular risk – lower concentrations of the micronutrients are associated with increased risk of age-related health problems including Alzheimer's disease.

“This is one of the first times a study of this type has focused only on older adults,” says co-author Alex Michels, a researcher at OSU's Linus Pauling Institute. “We wanted to fill in a piece of the puzzle – can hazelnuts improve the nutritional status of older adults specifically?”

Few hazelnut studies have involved Oregon hazelnuts, which account for 99 percent of US production of a nut also known as the filbert, Michels notes, adding however that the researchers do not believe Oregon hazelnuts are much different than other sources.

Maret Traber, the study’s corresponding author, notes that she and her collaborators used a novel biomarker – an alpha tocopherol metabolite – to determine whether hazelnuts had improved the research subjects’ vitamin E levels.

“It's hard to determine changes in α-tocopherol levels in the blood of older adults because they tend toward elevated cholesterol levels which leads to more α-tocopherol being retained in the blood,” says Traber, a professor in the OSU College of Public Health and Human Sciences and the Ava Helen Pauling Professor at the Linus Pauling Institute.

“So what we did instead was look at the urine to see how much of a vitamin E catabolite was in it. The catabolite should only increase if the body is getting enough vitamin E.”

The catabolite is alpha carboxyethyl hydroxychromanol, abbreviated to α-CEHC.

“It's basically a vitamin E molecule where the tail has been chewed up into nothing, part of the natural breakdown process of vitamin E as the body uses it," Michels says. "We saw urinary α-CEHC levels go up in almost every participant.”

Blood analysis further showed decreases in glucose and low-density lipoproteins, also known as “bad” cholesterol, in addition to increases in magnesium.

“The findings demonstrate the power of adding hazelnuts to your diet, of just changing one thing. Vitamin E and magnesium are two of the most underconsumed micronutrients in the US population, and there’s much more to hazelnuts than what we analyzed here,” Traver says, adding that for people who don’t like taking multivitamins, hazelnuts represent a “multivitamin in a natural form.”