Research Shows No Contribution of Nuts to Weight Gain

Research Shows No Contribution of Nuts to Weight Gain

Photo Credit: Maddi Bazzocco via Unsplash

Evidence from U of T study demonstrates that nuts do not contribute to weight gain

By Sharon Lee, Associate News Editor

Researchers at the University of Toronto (U of T) recently conducted a study which found that nut consumption does not contribute to weight gain.

The researchers concluded that higher nut intake is associated with reductions in body weight and body fat. They also found no increased risk of obesity or other measures of adiposity when consuming nuts.

To get the results, the researchers looked through 121 prospective studies and clinical trials that focuses on the relationship between obesity and nuts. They reviewed relevant data from each report, then used the system Grading of Recommendations Assessment, Development, and Evaluation (GRADE) to grade the validity of the evidence from each study.

How does it work?

In an email to The Mike, lead author Dr. Stephanie Nishi explained the mechanism behind the association of nuts and low weight gain. Nishi wrote that “The physical structure [of nuts] may lead to reduced bioaccessibility. Bioaccessibility refers to the amount of a nutrient that is released from the food to be absorbed and used in our bodies.” 

Nishi explained that consuming almonds results in higher excretion of fat and energy in fecal samples, which lowers fat and energy bioaccessibility. This reduction in bioaccessibility may be an explanation for why nuts, despite their high energy density, do not lead to weight gain.

Feelings of being full after consuming nuts may also contribute to reduced weight gain. “Nuts contain protein and fiber which are dietary components associated with increased feelings of satiety,” explained Nishi. “The physical structure of nuts may also contribute to their satiating effect because the act of chewing to break down the physical structure of nuts may modify appetite sensations.”

Where did the misconception of nuts and weight gain come from?

Nishi also addressed the misunderstanding in popular media about the association between nuts and weight gain. According to Nishi, dietary and clinical practice guidelines recommend nuts for their health promoting properties, but nuts are known to have high fat and dense calories. The conflicting messages raise concern because consuming foods high in calories implies weight gain and increased waistlines.

“In the case of nuts, a calorie may not be a calorie,” wrote Nishi. “What we are referring to is that for nuts, a calorie label [on a nutrient facts table] may not necessarily be the number of calories that are accessible to the body.”

Nishi called the unwarranted concern from the media a “missed opportunity” because nuts contain many nutrients including plant-based protein, fiber, vitamins, and minerals. Dieters must consume different nutrient-dense foods to ensure that their bodies have enough resources for proper functioning and for support of a good-quality life. Nuts are also considered “heart healthy” because their consumption is associated with reduced risks of cardiovascular mortality and lower cardiovascular events.

Healthy eating

As a method to approach healthy eating, Nishi listed several ways to encourage consumption of nuts.

“There are a variety of ways nuts may be incorporated into daily eating, such as by replacing a less nutrient-dense snack or food item (such as cookies or chips) if these are usually consumed. Nuts can also … be mixed in to hot or cold cereals or yogurt parfaits for breakfasts or snacks; for lunches or dinners nuts could be sprinkled on top of salads, soups, or pastas, sauteed with vegetables, or pack a handful of nuts with an apple or other fruit for a snack on-the-go.”