Nuts are loaded with nutrition but they’re also a calorie-dense food. For example, ten to twelve whole macadamia nuts, one of the highest calorie varieties, has over 200 calories. In fact, all nuts are relatively high in calories. Here’s the problem. Nuts are notoriously hard to stop eating. The combination of salt and fat is an enticing combination that keeps you dipping your hand back into the container for another round. It’s easy to lose track of how many you’re eating!
Based on the calorie density of nuts and the fact that it’s hard to control how many you eat, you might think that eating nuts would be a sure-fire recipe for weight gain. Makes sense from a calorie standpoint, doesn’t it? Yet, most studies show this isn’t the case. In fact, a number of studies show that adding nuts to a diet has no impact on weight control. Being so calorie dense, you would expect otherwise. Why might this be?
Why Nut Consumption Isn’t Linked with Weight Gain
There are several reasons why eating nuts aren’t linked with weight gain, despite being high in calories. One is the satiety factor. Nuts are not only rich in heart-healthy fats but they’re a good source of protein and fiber, two dietary components strongly linked with feelings of satiety. One study showed that when subjects ate nuts prior to a buffet-style meal, they consumed fewer calories when given the opportunity to eat unlimited quantities of food. Other studies show that the calories you take in from nuts, you compensate for by eating less of other foods.
Another interesting observation, based on research, is the observation that nuts increase resting energy expenditure. In other words, when you eat nuts, it elevates your metabolism and you burn more calories than you would eating a non-nut food. When you eat something, your metabolism temporarily increases to supply the energy needed to break down and absorb that food, a phenomenon called the thermal effect of food. Foods high in protein tend to cause a greater rise in the thermal effect of food than carbohydrates or fats. It appears that nuts have a significant impact on this component of energy expenditure.
The final factor that may reduce the impact energy-dense nuts have on body weight is the degree to which they’re absorbed. A number of studies show you don’t absorb all of the potential calories from nuts. This has been demonstrated with almonds and pistachios and likely holds true for other nuts as well. These studies show that about 20% of the calories in nuts aren’t absorbed, partially because their cells have tough walls that are resistant to digestion and breakdown.
Why Eat Nuts Anyway?
The fact that nuts are satisfying and don’t seem likely to cause weight gain works in their favor, but the benefits of eating nuts go far beyond this. Research shows a clear link between nut consumption and a lower risk of heart disease and dying prematurely. For example, a study published in the New England Journal of Medicine followed over 100,000 men and women. They found those who ate an ounce of nuts daily had lower mortality, were leaner, and had a smaller waist size. Research even shows that nuts have favorable effects on metabolic health and may lower the risk of metabolic syndrome and type 2 diabetes.
Other ways nuts may reduce the risk of heart disease is by their cholesterol-lowering capabilities. Studies also show that eating nuts may ease inflammation, a phenomenon also linked with heart disease and stroke.
How many nuts do you need to eat daily to get the benefits? Most experts recommend eating a handful daily or, at least, most days of the week. You don’t have to buy expensive tree nuts, the less costly peanut, actually, a legume offers similar benefits. If you’re trying to limit the number of calories you take in, pistachios are the lowest calorie tree nut with about 160 calories in 48 pistachios. When you consider that you don’t absorb all of the calories from pistachios, it’s even lower.
Choosing Nuts that Offer the Most Benefits
Is one nut healthier than the other? It appears that all nuts have health benefits, so you can’t go wrong nibbling on any of them. Macadamia nuts and pecans are a little higher in calories and fat than other nuts while almonds have more calcium than the others and are known for their higher amounts of vitamin E.
Walnuts, due to their higher content of omega-3s, help to balance out the omega-6s so abundant in the Western diet. Brazil nuts are an exceptional source of the trace mineral selenium. Cashews and pistachios are a bit higher in carbohydrates than other nuts. Your best bet is to eat a variety.
Are raw nuts better than roasted? Roasted taste better but are often heavily salted. The combination of salt and fat makes it harder to stop eating them. Plus, the healthy fats in nuts go rancid more quickly if you roast them. So, raw nuts may have a slight advantage in terms of health benefits. So, raw and unsalted may be best. You can always add your own blend of spices at home.
The Bottom Line
Yes, nuts are high in calories but they don’t appear to increase the risk of weight gain due to the factors discussed. Even more importantly, eating them is linked with a lower risk of heart disease and mortality. So, enjoy nuts – they’re better for you than other salty snacks and much healthier than snacks made from white flour and sugar.
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