Almonds improve appetite-regulating hormones in overweight adults, flags study

06 Dec 2022 --- New research delving into the benefits of almonds regarding weight management has addressed the multifaceted challenge of overweight and obesity. The study funded by the Almond Board of California demonstrated how almond consumption helped improve crucial appetite-regulating hormones concerning adults who are overweight or obese.

Appetite regulation and weight management are complex topics. People eat not only for hunger but for various other reasons, such as stress, boredom and excitement. All of these factors can contribute to someone having to deal with obesity.

Research from nutrition scientists in Australia set out to better understand why consuming almonds may lead to effective weight management. Dr. Alison Coates and her collaborators studied how almonds affect appetite, focusing on the hormones that help with regulation.

Assisting weight management 
The rates of overweight and obesity are a growing public health concern. Modulating appetite through better hormonal responses is a promising approach for assisting weight management. 

Research continues to explore how almonds can be a simple, effective addition to weight loss plans. A paradox of these tasty treasures is that almonds’ caloric density does not increase body weight, body mass index or body fat and may decrease waist circumference.

“Different foods impact people differently,” says Dr. Coates, professor of Human Nutrition and Director of the Alliance for Research in Exercise, Nutrition and Activity at the University of South Australia. 

“Calories are important, but we think there’s more to the story than that. Our understanding of almonds is evolving as nutrition researchers apply the scientific method to explore these important topics.”

According to Coates, consumers who eat tree nuts, like almonds, have a lower risk of obesity. The rates of overweight and obesity are a growing public health concern.

“We wanted to dig into what is so special about almonds. We thought something beneficial must happen on a hormonal level when almonds are added to the diet.”

In her research, Coates hypothesized that almonds would have “a favorable effect” on the hormones that regulate appetite and impact the study participants’ perception of their appetites. 

Furthermore, the researchers wanted to know if an almond snack would help reduce subsequent consumption of calories compared to a standard carbohydrate-based snack.

Study settings 
The study involved 140 individuals who were overweight or obese (42 males, 98 females), aged 47.5 years (+ 10.8 years). 

Participants consumed unsalted, whole, natural almonds with skins (experimental group) or an oven-baked fruit cereal bar (control group). They measured their levels of appetite-regulating hormones and self-reported appetite ratings over a two-hour period. 

The almond portion provided was approximately 30 to 50 g of almonds, depending on which calorie level the participant followed. 

A subset of participants was then invited individually to dine freely at a buffet for 30 minutes. Researchers explored if almond consumption, compared to the carbohydrate snack, influenced how much people would consume from the buffet.

Researchers measured appetite-regulating hormones: ghrelin, glucose-dependent insulinotropic polypeptide, glucagon-like peptide-1, leptin, pancreatic polypeptide, peptide YY, C-peptide, glucagon and cholecystokinin. 

Insulin and glucose response 
The C-peptide response was 47% smaller with almonds than with the carbohydrate snack (p < 0.001). Decreased C-peptide activity indicates lower insulin response, which may have implications for the development of diabetes and cardiovascular disease. 

Almonds may reduce the glucose response and, over time, help reduce insulin resistance when consumed with a high-carbohydrate food or meal. Additionally, glucose-dependent insulinotropic polypeptide, glucagon and pancreatic polypeptide responses were larger with almonds versus the carbohydrate snack. 

Glucagon promotes satiety and may encourage weight loss, while pancreatic polypeptide lowers appetite, reduces food intake and helps food remain in the stomach longer.According to Coates, consumers who eat tree nuts, like almonds, have a lower risk of obesity.

Cholecystokinin, ghrelin, glucagon-like peptide-1, leptin and peptide YY responses were not different between the almond or the snack bar groups. Neither did self-reported appetite ratings differ significantly between the groups. However, the group treated with almonds consumed about 100 fewer calories at the buffet, although the finding was not statistically significant (the exact calorie reduction was 72 calories).

Consuming fewer calories may be important clinically and for public health when viewed over extended time across populations. 

“Think about what the calorie reduction each day over a year would mean for weight management,” explains Coates. “That would contribute to a positive reversal in the gradual, nearly imperceptible weight gain many people experience yearly, compounded over a lifetime.”

More from future studies
While the findings from this research are encouraging, there are some limitations to consider. A COVID-19 overlay resulted in restrictions on the number of participants who could complete the buffet challenge. 

In addition, as noted before, all participants had elevated body weight. Future research could examine how healthy-weight individuals respond to almond snacks and provide insight into the possible prevention of overweight and obesity. 

Lastly, the research team recommends that future studies investigate implications for longer-term appetite regulation.

Moreover, the study indicates almond consumption resulted in improved hormonal responses, reflecting better insulin release control and blood glucose regulation. Regular almond consumers may also be more likely to consume fewer calories and manage weight better.

In similar developments, researchers recently revealed that just four weeks of eating mixed tree nuts could positively affect mood, memory and overall thinking capability. Eating nuts can help to modulate metabolites, bacteria and microbes in the gut. 

Meanwhile, two separate studies out of Penn State University showed that adding peanuts, herbs and spices to the average American diet can increase the abundance of gut bacteria associated with better health. 

The research found that adding a daily ounce of peanuts or about a teaspoon of herbs and spices to diets may affect the composition of gut bacteria – an indicator of overall health.

Edited by Elizabeth Green