We know that nuts are a nutrient-dense food but a calorie-dense one as well. It’s easy to sit down with a jar eating nuts by the handful and knock down 400 calories, especially if you don’t ration the amount you eat – and it doesn’t take a lot of nuts to consume hundreds of calories. But, despite their calorie density, studies show that nut eaters tend to be leaner. Surprised? We equate calorie-dense foods with weight gain but eating nuts seem to be an exception? Why might this be?
More and more studies suggest that it’s not just calories that matter but the quality of the calories you eat – and nuts are a high-quality source of nutrients and energy. Let’s look at some of the reasons they, despite their high calorie-density, may help you control your weight rather than add inches to your bottom line.
You Don’t Absorb All of the Fats When Eating Nuts
We know that getting enough dietary fat is important for health and that not all fat is unhealthy – but it is a dense source of calories. Fat has around 9 kilocalories per gram compared to only 4 grams per kilogram for carbohydrates and protein – and we know that nuts are high in fat. Here’s the kicker. Studies show that we don’t absorb all of the fat in nuts. As much as 20% of the fat from sources like almonds and pistachios is excreted from your body without being absorbed. So, when you read the calorie count on a jar of nuts, it’s actually lower than what is stated when you consider how many are actually bioavailable. Almost everyone loves free calories, right? You get them when you eat nuts.
Eating Nuts is Satiating
Nuts have the full factor working in their favor too. Research shows nuts are satiating food and satisfy hunger more than rapidly absorbed carbs that most people snack on, such as potato chips. The reason? Nuts are a good source of fiber and protein, two components that enhance satiety. Research has specifically looked at the impact of two types of nuts on appetite, peanuts, and almonds. These studies show that people eat less later in the day after snacking on these nuts. It likely holds true for other nuts as well.
One caveat, nuts combine fat and salt and that gives them good “mouth feel” and makes them pleasurable to eat. Even if nuts are satiating, the gratification of eating them can lead to overindulgence. So, it’s still better to set aside a handful and put away the bag or can before you suddenly realize you’ve eaten several servings without even realizing it!
Eating Nuts May Boost Energy Expenditure and Fat Oxidation
We know that the food we ate causes a transient bump-up in metabolism, called the thermic effect of food. Studies suggest that nuts may cause a more pronounced boost in metabolism relative to other foods. In fact, one study found that consuming a snack of walnuts increased energy expenditure more than a comparable dairy meal, However, a snack of peanuts or almonds didn’t produce the same effect in the study. There’s also some evidence that walnuts increase fat oxidation, although more research is needed to confirm this. It’s not clear why this might be, although researchers propose that the polyunsaturated fats in walnuts may have metabolism-boosting effects, based on prior studies.
Can Eating Nuts Reduce Inflammation
Another benefit of eating nuts, backed by research, is their anti-inflammatory effects. In fact, a study found that eating nuts is linked with a lower level of c-reactive protein, a blood marker of inflammation. Studies also associate eating nuts with reduced risk of insulin resistance and metabolic syndrome. Once insulin resistance enters the scene, it becomes even more challenging to lose weight as higher levels of insulin block fat breakdown. Eating nuts may help maintain healthy insulin sensitivity and, thereby, reduce the likelihood of gaining body fat.
Is One Nut Better Than Another?
All tree nuts appear to have health benefits and even peanuts, not technically a nut, is linked with desirable benefits, like a reduction in cardiovascular disease. So, you can’t go wrong eating any nut. However, considering the available studies, walnuts have characteristics that make them especially appealing. As mentioned, walnuts are potentially linked with increased energy expenditure and fat oxidation. Plus, walnuts are one of the best, plant-based sources of omega-3s, a type of fat that may help reduce inflammation.
How many nuts should you eat at a time? To get the health benefits, most experts recommend enjoying a small handful of mixed nuts each day, as each nut has its own unique benefits. For example, Brazil nuts are exceptionally high in the trace mineral selenium, while almonds are packed full of vitamin E. Walnuts and macadamia nuts are an excellent source of heart-healthy fats, walnuts being high in omega-3s and macadamia nuts monounsaturated fats, like those in olive oil. Pistachios have the distinction of being the nut lowest in calories, while peanuts contain the highest levels of an antioxidant called resveratrol. Pecans rank high on the antioxidant scale. So, you’re getting health benefits no matter what type of nut you bite into. Why not eat a little of each? Variety is good when it comes to nuts.
The Bottom Line
Nuts are a virtuous snack. We know that they have health benefits, particularly for cardiovascular health – and if you’re worried about the calories, nut consumption is not linked with weight gain. Still, you can eat too much of even the healthiest foods. So, watch your portions. Use them as a healthier snack to replace less desirable ones such as chips, cookies, or candy. Raw or roasted, it doesn’t matter how you cook them up, nuts are a snack-worthy addition to your diet.
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