Evidence is increasingly being published in authoritative scientific journals and newspapers to support how regular consumption of nuts can contribute to the prevention of various chronic diseases such as cardiovascular disease and type 2 diabetes.
Together with awareness campaigns carried out by health experts such as doctors and nutritionists, this has undoubtedly contributed to the significant increase in consumption of oily nuts that has occurred worldwide in recent years among consumers interested in a balanced diet.
Despite this, however, there is still a good percentage of people who choose not to introduce nuts into their diet: why? The idea that nuts are a high-calorie food and therefore fattening.
In this article we will try to dispel this myth. Nuts (walnuts, hazelnuts, almonds, etc.) have a rather high fat content, which depending on the type of nut ranges from 45% to 75% of the total composition and for this reason it is actually a food that provides many calories (high energy density). However, the aspect that is not taken into account is that, in contrast to what can be thought of, if consumed in the right portions and included in a balanced Mediterranean diet, accompanied by regular physical activity, does not fatten and provides at the same time useful nutrients for the well-being of the body such as unsaturated fat, protein, fibre, vitamins, minerals and compounds with antioxidant action.
This is what emerges from several controlled clinical studies that showed no significant weight changes in people who regularly eat nuts, but on the contrary in some cases there was an unexplained weight loss. In a review published in 2007 in The Journal of Nutrition, hypotheses were made about the mechanisms responsible for weight loss associated with nuts consumption:
- Sense of satiety: nuts have a high satiating power. This property is very important in the management of body weight because the reduction of the sense of hunger can prolong the timing between meals; a decrease in the desire to eat can prevent eating in the absence of hunger and the sense of satiety, on an empty stomach, can result in more controlled meals. The dominant cause of satiety has not yet been identified: it is probably a combination of factors to which the unsaturated fat content, fibre and low glycemic index also contribute. This aspect makes nuts an excellent snack to be eaten as a mid-morning or mid-afternoon snack, away from meals.
- Low energy absorption efficiency: although nuts contain a lot of fat, it is not fully absorbed by the body. A part of it, in fact, passes unharmed through the digestive system and are eliminated. This inefficiency derives from the resistance of the cell walls of nuts to the action of intestinal bacteria and enzymes: the cells that do not break during chewing pass through the gastrointestinal tract without releasing the fats they contain.
- Increased energy consumption: the regular consumption of nuts seems to increase energy consumption due to basal metabolism. This basically means that consuming nuts on a daily basis stimulates the body to burn more calories, an interesting aspect that has yet to be further investigated and more in-depth studies will be needed to confirm this.
A review published in 2011 in Nutrition, Metabolism and Cardiovascular Diseases collects the results of several studies on the impact of oily nuts on body weight over an extended period of time (i.e. more than 1 year). The conclusions drawn seem to confirm that the consumption of nuts, even in the long term, is not associated with a higher risk of obesity or weight gain.
These data suggest that there are no "fattening" foods and that each food must be evaluated objectively for its impact on body weight and total dietary quality. In this case, in particular, it is always the portions that make the difference between a healthy product and a fattening product: it is clear that by eating more calories than needed the excess calories must be "stored".
When substantial amounts of a high-calorie food are introduced into an already high-calorie diet without any kind of compensation or balancing and without making full use of the calories ingested (e.g. physical activity) the logical consequence is weight gain. The LARN (Nutrient and Energy Reference Intake Levels for the Italian population) suggest a 30g portion that according to the guidelines of the Mediterranean diet should be consumed every day, this standard dose may vary according to the nutritional needs and dietary choices of each individual.
On Nuturally you can find 120 natural nuts and dried fruit with no added sugar, that are ideal for your daily snack.
Sources:
http://www.nucisitalia.it/benefici-consumo/peso-corporeo/
M.A. Martínez-González, M. Bes-Rastrollo; Nut consumption, weight gain and obesity: Epidemiological evidence; Nutr Metab Cardiovasc Dis.; Volume 21, Supplement 1, June 2011, Pages S40-S45.
Richard D. Mattes, Penny M. Kris-Etherton, Gary D. Foster, Impact of Peanuts and Tree Nuts on Body Weight and Healthy Weight Loss in Adults, The Journal of Nutrition, Volume 138, Issue 9, September 2008, Pages 1741S–1745S.
Sze Yen Tan, Jaapna Dhillon, Richard D Mattes, A review of the effects of nuts on appetite, food intake, metabolism, and body weight, The American Journal of Clinical Nutrition, Volume 100, Issue suppl_1, July 2014, Pages 412S–422S.
