Are All Calories Created Equal? A New Study Shows A Serving Of Almonds Can Help You Feel Full, Without Leading To Weight Gain

Main Category: Nutrition / Diet
Article Date: 20 Sep 2007 - 14:00 PDT

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Scientists have noticed for many years that people who regularly eat almonds tend to weigh less than people who do not - even though they tend to eat more calories over the course of a day.1 Why? A new study published in the British Journal of Nutrition sheds light on the mechanisms behind almonds' ability to provide valuable nutrition and help lower LDL cholesterol levels without contributing to weight gain.

In the study, women were instructed to eat 344 calories worth of almonds (around 56 grammes) every day for one 10-week period, and then eat their customary diet for another 10 weeks. The women did not gain weight during the period they consumed almonds. In addition, because of the high Vitamin E and magnesium content in almonds, they met the daily dietary recommendations for these two nutrients.

The researchers determined that the study participants felt satisfied, so they naturally compensated for most of the calories in almonds by reducing their intake of other foods in their normal daily diet. They also noted a decrease in total carbohydrate intake, suggesting almonds may have replaced carbohydrate-rich foods.

Additionally, the researchers found that the fibre in almonds appears to block some of the fat they contain from being digested and absorbed. This means that almonds may provide fewer calories than would be expected. This raises broader questions about the availability of energy from foods.

"Solid data has shown that eating one to three daily portions of almonds (28 to 84 grammes) can help lower LDL cholesterol levels," said study co-author Rick Mattes, Ph.D., R.D. from Purdue University in West Lafayette, USA. "But many health care providers have been hesitant to recommend almonds as a daily snack because they're a relatively high-calorie food and could contribute to weight gain. This study challenges that assumption."

Study Details

The research team at Purdue University conducted a study with 20 women, most of whom were overweight. One group was instructed to eat a normal diet for 10 weeks, but make one change - add 344 calories worth of almonds every day, around 56 grammes. The other group was instructed to eat their customary diet and no almonds. The groups then took a break for three weeks, and switched, so the second group ate almonds and the first group ate none. Researchers measured body weight, metabolic rates, and physical activity at various points during the study. Compliance to almond consumption was assessed through diet records, as well as by measuring blood levels of Vitamin E. This measurement was used because eating almonds, a leading source of Vitamin E, has been shown to increase Vitamin E levels in the blood.

The researchers found that when people were eating the 344 calories worth of almonds every day they were, in total, only taking in an extra 77 calories. This is because the participants naturally compensate for the great majority of the calories in almonds, about 74 percent, as they found them to be satiating, or satisfying.

A further portion of these extra daily 77 calories was offset because the fibre structure of almonds blocked the fat in almonds from being fully absorbed. Although not statistically significant, the researchers also noted an increase in energy expenditure through an increase in resting energy expenditure, the number of calories used while participants were at rest. Based on the various measures in the study, the researchers concluded that the calories from almonds were compensated for by natural reduction in the consumption of other foods, by some of the fat from the almonds passing through the body without being digested, and by an increase in resting energy expenditure.

Also notable was that eating almonds led to significant increases in the intake of several important nutrients: monounsaturated and polyunsaturated fat, Vitamin E, magnesium and copper.
v "This study further demonstrates that almonds are not only nutritious, they can be satisfying - a good choice in place of something less nutrient-rich and less filling" commented Dr Tony Leeds, Senior Lecturer in Nutrition at Kings College London.

Building on Previous Research

This study adds to the evidence that almonds are satiating and may play a valuable role in weight management. Previous studies have shown that the addition of nuts, and almonds specifically, to a daily diet does not cause weight gain and increases satiety.1 In fact, almonds have been included in amounts up to 570 calories a day without contributing to weight gain.1 Recent research has also shown that almonds may help reduce spikes in blood sugar following a carbohydrate-based meal. High blood sugar levels often lead to a feeling of hunger which can prompt people to eat more than they should. 1,2

A 28 gramme, 160-calorie handful of almonds is an excellent source of Vitamin E and magnesium, a good source of protein and fibre, and offers potassium, calcium, phosphorous, iron, and monounsaturated fat. For additional information about almonds, including easy recipes and snack ideas, visit http://www.AlmondsAreIn.com.

Summary of Published Study:

- Journal: British Journal of Nutrition, September 2007

- Research Organizations: Purdue University, West Lafayette, Ind.

- Study Title: Effect of chronic almond consumption on body weight of healthy humans.

- Authors: James Hollis, PhD; Rick Mattes, PhD, RD

- Objective: To determine if the inclusion of a 344 calorie serving of almonds in the daily diet results in positive energy balance, and body composition change.

- Subjects: 20 women with an average age of 24 and an average BMI of 25

Study description: In this 23 week crossover study, participants were randomized to one of two conditions, almonds or control. The almond group was instructed to consume two ounces of raw, unsalted almonds for 10 weeks in addition to their normal daily diet. The control group followed their usual diet. After 10 weeks and a three week washout period, the groups crossed over (the almond group became the control and vice versa). Body weight, metabolic rates, and physical activity were measured during weeks one and eight. Stool samples and serum vitamin E levels were also measured.

Results: Ten weeks of almond supplementation did not cause a change in body weight despite an overall increase in caloric intake. Seventy-four percent of the calories in almonds were compensated for through reduced food intake from other sources. Inefficiency in the absorption of energy from almonds was also observed. The fibre structure of the almonds appears to block the fat in almonds from being fully available. No changes in physical activity or metabolism were noted. In addition, the consumption of almonds led to a significant increase in the intake of polyunsaturated fat (4.4 g, p<.05), monounsaturated fat (16.9 g, p<.05), vitamin E (35.6 mg, p<.05), magnesium (18.3 g, p<.05), and copper (9.4 mg, p<.05).

Conclusions: A daily serving of two ounces of almonds may be included in the diet without weight gain and may help increase the intake of unsaturated fats and essential nutrients, including vitamin E, magnesium and copper.

References:

1) Rajaram S and Sabate J. Nuts, body weight and insulin resistance. Br J Nutr. 2006 Nov; 96 Suppl 2:S79-86.

2) Jenkins et al. Almonds decrease postprandial glycemia, insulinemia, and oxidative damage in healthy individuals. J Nutr. 2006 Dec; 136(12):2987-92.

The Almond Board of California welcomes the participation of all industry members and does not discriminate on the basis of race, colour, national origin, sexual orientation, gender, marital status, religion, age, disability or political beliefs.

http://www.AlmondsAreIn.com

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