Nuts May Improve Weight Loss and Blood Sugar Levels in Calorie-Restricted Diets: Study

In a recent review published in Nutrition Research Reviews, researchers compared the effects of energy-restricted (ER) dietary patterns with nuts or without on body composition, weight, and glycemic management.

Nutritionists often recommend energy-restricted (ER) diets to achieve weight loss, improve body composition, and manage blood sugar levels. However, one of the challenges with ER diets is maintaining high diet quality while ensuring the intake of essential nutrients.

Nuts, known for being nutrient-dense, can play a crucial role in meeting these dietary requirements. They are rich in essential fatty acids (EFAs), which can improve glycemic management by reducing pro-inflammatory cytokines and insulin resistance. Their low carbohydrate and high unsaturated fat, fibre, B vitamins, magnesium, and protein content help increase fat oxidation, slow gastric emptying, and lower postprandial glucose levels. Additionally, nuts enhance satiety, preserve muscle mass, and mitigate the reduction in resting energy expenditure typically associated with weight loss.

The impact of nut consumption on glycemic indices—measures of blood sugar levels—varies across different studies. This inconsistency exists in both healthy individuals and those with conditions such as metabolic syndrome, dyslipidemia, or prediabetes. Some research suggests that nuts can positively influence blood sugar control, while other studies do not show significant effects.

For the study, researchers investigated the effects of incorporating nuts into a calorie-restricted diet on body measurements and glycemic control in overweight or obese individuals. They analysed randomized controlled trials (RCTs) to compare the impact of energy-restricted diets with or without nuts on body mass, composition, and blood sugar management.

The RCTs included overweight individuals with or without comorbidities who were undergoing weight loss treatments. The studies measured blood glucose levels using various methods, including venous blood draws, finger pricking, flash glucose monitors, and continuous glucose monitoring (CGM).

The results showed that a nut-enriched energy-restricted (ER) diet led to a weight reduction of -22.6 to -19.5 kg, or approximately -0.1 to -0.2 kg per week. The additional benefit of incorporating nuts into the ER diet varied between -1.4 to 0.4 kg. Significant variations between trials included the timing of nut supplementation, the types of nuts consumed, and the methods used for anthropometric measurements.

The research found limited evidence to support the advantages of nuts for body composition or glycemic management. While advantages in weight reduction and glycemia were variable when adding nuts to energy-restricted diets, there were no adverse effects. All trials found that an energy-restricted diet improved body mass with variable effects on glucose and insulin.

Reference: Mead LC, Hill AM, Carter S, and Coates AM. Effects of energy-restricted diets with or without nuts on weight, body composition, and glycaemic control in adults: a scoping review. Nutrition Research Reviews. Published online 2024:1–17. doi:10.1017/S0954422424000106