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Eating nuts every day does not cause weight gain, but it does improve health

In the midst of evolving dietary trends and endless health advice, a common misconception persists: eating nuts, particularly tree nuts like pistachios, leads to weight gain due to their fat content.

This belief has contributed to more than half of Americans falling short of the recommended 5–7 ounce equivalents of nuts and seeds per week.

However, recent studies and expert opinions are challenging this myth, revealing the beneficial impact of nuts on health without the feared weight gain.

Misunderstood nutritional powerhouse

The hesitation to incorporate nuts into the daily diet often stems from their perceived high calorie and fat composition.

Contrary to popular belief, up to 87% of Americans are concerned about nut-induced weight gain, overlooking the scientific consensus that daily consumption of nuts, including pistachios, is a viable strategy to combat various health conditions.

These conditions, exacerbated by excess weight, range from diabetes to heart disease.

The concern is particularly significant among young adults in their 20s and 30s, who are increasingly experiencing metabolic syndrome (MetSx) — a cluster of conditions that heighten the risk of developing prediabetes and diabetes. Alarmingly, the prevalence of MetSx has surged to 21.3% within this demographic.

Reexamining nut consumption and weight gain

The dawn of the New Year brings an opportunity to dispel enduring food myths, especially those surrounding the fat content of nuts.

A comprehensive study by Heidi J. Silver, PhD, RD, and her team at Vanderbilt University Medical Center, offers compelling evidence.

The study involved 84 millennial-aged adults with at least one MetSx risk factor, who were given either a daily snack of mixed tree nuts, including pistachios, or a carbohydrate-based snack, without altering their diet or lifestyle otherwise.

Remarkably, the study found a significant reduction in MetSx risk — 67% for females and 42% for males — among those consuming tree nuts.

Moreover, there was no observed increase in energy intake or body weight over the 16-week period.

Beyond weight: Nutritional benefits

These findings align with previous research indicating that consuming a substantial portion of calories from pistachios does not result in weight gain.

Notably, female participants saw a decrease in waist circumference, while male participants experienced reduced blood insulin levels, underscoring the potential of tree nuts to mitigate key risk factors for diabetes and heart disease.

Pistachios, in particular, stand out not only for their weight management potential but also for their nutritional profile.

As a plant-based source of complete protein, pistachios offer a remarkable blend of nutrients, including fiber, vitamin B6, thiamin, phosphorus, and copper.

This makes them an excellent choice for a nutritious snack that can help maintain energy levels and support overall health. This evidence challenges the entrenched notion that nut consumption leads to weight gain.

Embracing nuts without gaining weight

Heidi J. Silver emphasizes the study’s rigorous design, highlighting its contribution to understanding the impact of tree nut consumption on body weight.

“We specifically designed the study to be able to investigate the independent effects of eating tree nuts on body weight by ensuring that the number of calories the participants ate during the 16-week intervention period matched the amount of calories they expended each day, which is one of the overall strengths of the study design and results,” explained Silver.

She advocates for incorporating tree nuts like pistachios into one’s diet as a part of a healthy self-care routine in 2024 and beyond.

“This carefully designed and well-controlled study shows that eating tree nuts, like pistachios, does not have to lead to weight gain and can be an important part of anyone’s self-health care routine,” she explains.

While further research is needed to explore the cardiometabolic response to tree nuts across different population subgroups, the current findings are a testament to the role of nuts in a balanced diet.

Let this New Year be the turning point in embracing the flavorful, nutritious, and satisfying addition of tree nuts to your diet, debunking myths, and prioritizing your health.

The full study was published in the journal Nutrients.


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