By Michael R. Williams, RD
Successful weight loss is centered upon consuming fewer calories than the body burns. This is based on the notion that eating too many calories causes the body to store the excess energy as body fat. By cutting back on calories, the body will burn fat to make up energy needs. One of the most common ways of cutting calories is to eat less high-fat foods, which contain large levels of calories in a form that is easily stored on the body. Therefore, there was much shock when nutrition and food scientists discovered that nuts, a high-fat and high-calorie food can actually help with weight loss.
Nuts aid weight loss in a few different ways. The most widely understood role is in the regulation of appetite. Research over the last two decades has shown that eating nuts leads to an increased feeling of fullness. As noted by Dr. Richard Mattes, professor of nutrition science at Purdue University and a leading expert in energy balance, reports that eating nuts can help offset the calorie intake later in the day by up to 75 percent. He notes that even a small handful of nuts can help stave off hunger for hours, which is due to rich protein and fiber content — two nutrients that are heralded as the most “fullness inducing.” This is perhaps where nuts really shine, as they are one of a few foods to have high levels of both.
However, even with the high fiber and protein levels, nuts are still very high in fat. This begs the question: How can a high-energy, dense food not lead to weight gain? Recent research has determined that due to their molecular structure, nuts are resistant to digestion within the small intestine. Basically, nuts which are not completely chewed are not easily absorbed and will pass through the digestive tract, leaving around 20 percent of fat and calories unabsorbed by the body.
Additionally, there is preliminary research that nuts may increase metabolism. This evidence, while still sparse, suggests that eating nuts may increase the amount of energy burned by the body. To date, there have been three trials to support this. The most compelling finding demonstrates an 11 percent increase in metabolic rate (amount of calories burned) after regularly consuming peanuts for 19 weeks.
There is an increasing body of evidence in support of nuts as an integral part of a well-balanced diet. Previously, the concern over nuts as a high-fat and high-calorie food have now been replaced by increased feeling of fullness, decreased fat absorption and a possible increase in metabolism. Nonetheless, it is best to only consume a small amount as a little can go a long way. One cup (or about two handfuls) can easily carry over 800 calories, which can easily turn weight losses into gains. Therefore, it is recommended to snack on a small handful of nuts, especially in place of other nutrient poor snacks.