Will a diet containing nuts ; a food high in calories and fat; lead to weight gain? The surprising answer is no. In fact, adding nuts to your diet could even help you to lose weight. The natural assumption that nuts will cause weight gain has been challenged by a number of scientific studies examining the relationship of a diet containing nuts and body weight. Many studies have found that eating nuts actually doesn't cause an increase in body weight, and may even help you lose weight more easily and efficiently.

Two clinical trials, in which participants were provided with almonds to be eaten daily but given no instruction related to diet or lifestyle behaviors, found that eating nuts has little impact on body weight [1]. In both studies it was predicted that participants would gain several pounds with the addition of nuts to their diet, but in fact they gained little or no weight.

It seems clear that adding nuts to your diet doesn't necessarily mean gaining weight, but can eating nuts help you lose weight? Several clinical studies have found that, surprisingly, adding nuts to a weight loss diet can improve the diet's effectiveness [2, 3]. One trial examined the effectiveness of a weight loss program that included almonds with one including complex carbohydrates. This study, which included 65 adult participants, found that the group that consumed almonds lost more weight and had a greater decrease in Body Mass Index (BMI), waist circumference, and fat mass than those who were in the complex carbohydrate group. Another study found that a diet containing moderate amounts of fat, including fat from nuts, was more successful in terms of weight loss and adherence than a low-fat diet.

How Can Nuts Help You Lose Weight?

  • People who eat nuts report feeling much less hungry, indicating that some aspect of nut consumption helps to suppress hunger [4].
  • Eating nuts leads you to eat fewer calories at subsequent meals. It is estimated that anywhere from 65-75% of the calories provided by nuts are offset by spontaneously eating less later.
  • Large amounts of fat contained in whole nuts pass through the digestive tract without being absorbed by the body. Several studies have found that consuming whole nuts (as opposed to nut paste or nut oil) results in an estimated 10-20% of calories lost due to the limited efficiency of energy absorption. The cell walls of nuts appear to be resistant to degradation by gastrointestinal enzymes, meaning that any cells not broken through chewing may not release the fat they contain [5].
  • Eating nuts will increase your resting energy expenditure (REE) – the number of calories you burn while at rest. According to one trial, eating peanuts resulted in an 11% increase in REE. For example, a 30 year old woman who is 5 feet and 4 inches tall and weighs 160 pounds has a REE of 1511 calories per day, meaning that replacing some of her diet with nuts could lead to the burning of an extra 166 calories each day – a loss of 17 pounds per year if she doesn't replace these calories with additional food.

Although nuts are a food high in fat and calories, there is reason to believe that the addition of a moderate amount of nuts to your diet will not cause you to gain weight, and may in fact be a helpful part of a diet geared toward weight loss. Nuts make you feel fuller and eat less, contain fat that is difficult for the body to absorb, and can increase the number of calories you expend while your body is at rest. With all these advantages, it's no surprise that some of the best weight loss programs recommend you include nuts in your diet in order to gain and maintain a healthy body weight.


1. Hollis JH, Mattes RD. Effect of chronic consumption of almonds on body weight in healthy humans. Br J Nutr. 2007;98:651–6.

2. Rajaram S, Sabate J. Nuts, body weight and insulin resistance. Br J Nutr. 2006;96:S79–86.

3. Alper CM, Mattes RD. The effects of chronic peanut consumption on energy balance and hedonics. Int J Obes. 2002;26:1129–37.

4. Kirkmeyer SV, Mattes RD. Effects of food attributes on hunger and food intake. Int J Obes Relat Metab Disord. 2000;24:1167–75.

5. Ellis PR, Kendall CWC, Ren Y, Parker C, Pacy JF, Waldron KW, Jenkins DJA. Role of cell walls in the bioaccessibility of lipids in almond seeds. Am J Clin Nutr. 2004;80:604–13.

Author's Bio: 

Matt Papa, research assistant and postdoctoral fellow at Washington University School of Medicine, is interested in researching treatments for weight loss and sharing information of help to others. In his website Matt offers a coupon for Medifast, a medically approved diet program, and publishes articles on a variety of weight loss topics including how does Sibutramine work and information about the newly discovered non-invasive intragastric balloon treatment for the non too obese.