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Q: My daughter and I love eating nuts, especially during the holidays. But we usually try to hold ourselves back and refrain from eating them. I have metabolic syndrome and think that nuts probably aren’t good for my condition. My daughter thinks that they are fattening. Are we right about nuts?
A: No. The truth about nuts is quite contrary to what you and your daughter believe. According to the research, nuts and seeds are some of the best foods you can eat for overall health, metabolic syndrome, and weight loss!
To Avoid Nuts Is Just Plain Nuts
Most people don’t realize it, but a low intake of nuts in the diet is a major killer. The 2017 Global Burden of Disease Study, the most comprehensive analysis of the causes of death ever undertaken, involved nearly 500 researchers and examined nearly 100,000 data sources. The study calculated that not eating enough nuts and seeds was a leading dietary risk factor for death and disability around the world, killing more people than processed meat consumption, and more than low intake of fiber and vegetables. In fact, eating more vegetables could potentially save 1.8 million lives, but eating more nuts and seeds might save 2.5 million, according to the study. The research also found that the healthy foods missing from the most diets around the world actually are nuts and seeds!
What Makes Nuts So Healthy?
They’re a source of healthy fats, dietary fiber, and vegetable protein, and they also contain numerous heart-protective vitamins and minerals, including vitamin E, folic acid, niacin, vitamin B6, magnesium, zinc, copper, and potassium. Nuts contain the nonessential amino acid arginine, which plays an important role in protecting the inner lining of the arterial walls, and they also contain phytochemicals, biologically active plant chemicals with high antioxidant properties that help protect against disease.
Fewer Deaths From All Causes
Higher nut intake is also associated with less cancer risk and decreased risk of death from all causes, including diabetes, respiratory disease, neurodegenerative disease, and infections. The authors of the 2017 meta-analysis wrote: “These findings support recommendations to increase intake of nuts to reduce the risk of chronic diseases and premature mortality in the general population.”
Healthy Blood Sugar Levels
Research points to nuts being beneficial in the prevention and treatment of diabetes and metabolic syndrome. Nuts are low in carbohydrates and don’t raise blood sugar levels much. Therefore, substituting nuts for higher-carb foods is a good strategy for lowering blood sugar levels.
Several studies have shown that blood sugar, blood pressure, and other health markers improve when people with type 2 diabetes and metabolic syndrome include nuts in their diet. Research suggests that nuts may exert beneficial effects on metabolic syndrome by improving inflammation, the balance between free radicals and antioxidants, and impaired functioning of the lining of blood vessels. These mechanisms in turn can improve insulin sensitivity and secretion, and decrease the risk of diabetes, unhealthy blood lipid levels, abdominal obesity, and hypertension, all components of metabolic syndrome.
Prevent Metabolic Syndrome, a Prediabetes Condition
Eating nuts also lowers the risk of developing metabolic syndrome. One cross-sectional study of 13,292 participants reported that people who ate tree nuts and nut butter had a lower prevalence of metabolic syndrome and four of its components—abdominal obesity, hypertension, elevated blood sugar, and low HDL cholesterol—than those who didn’t eat these foods. A study conducted in 2013 found that people who consumed more than two servings of nuts per week had a 32 percent lower risk of metabolic syndrome than those who never or almost never consumed nuts.
A Strong Heart
Two large epidemiological studies—after adjusting for other coronary heart disease risk factors—linked the intake of five or more servings (five ounces) of nuts per week to a 35–50 percent reduction in risk of coronary heart disease incidence and death.
Staving Off Weight Gain—or Boosting It
Increasing nut consumption by just half a serving (½ ounce per day) is associated with less long-term weight gain and a lower risk for obesity in adults, according to a large, long-term observational study, published in the online journal BMJ Nutrition, Prevention & Health in 2019. Replacing unhealthy foods, such as processed meats, French fries, and potato chips with half a serving of nuts may be a simple strategy to stave off the gradual weight gain that often accompanies the aging process, the authors of the study write.
Even though nuts are a concentrated source of fat and calories, research indicates that eating moderate amounts of them either has no significant effect on body weight or actually helps prevent weight gain—and sometimes even promote weight loss.
In a study of overweight women, those eating almonds lost nearly three times as much weight and experienced a significantly greater decrease in waist size compared to those who didn’t eat them. The few trials that have contrasted weight loss through meal plans that include or exclude nuts indicate more compliance and weight loss when nuts are part of the diet.
Many researchers believe that nuts may help with weight control for the following reasons:
- Chewing nuts takes some effort, leaving less energy for eating other foods.
- The high fiber content of nuts delays stomach emptying, which provides a longer-lasting sense of satiety and fullness.
- A portion of fat stays trapped within the nut’s fibrous wall during digestion, and your body doesn’t absorb all of the calories in nuts. The Nutrition Facts on a package of almonds may indicate that a 1-ounce serving has 160–170 calories, but your body absorbs only about 129 of these calories.
- There is some evidence that the high unsaturated fat content of nuts increases resting energy expenditure, which may help ward off weight gain.
- Nuts have prebiotic properties: their high levels of fiber and polyphenols (types of phytochemicals) are metabolized by gut microorganisms, which helps improve gut microbiome balance and intestinal health. Researchers believe these effects also help with weight control.
What’s a Realistic Serving?
The key to reaping the benefits of nuts is to eat them in moderation. All it takes is a ½ oz. to 1 oz. serving daily up to five days a week. The following amounts equal 1 oz:
- 24 almonds
- 18 medium cashews
- 12 hazelnuts,
- 8 medium Brazil nuts
- 12 macadamia nuts
- 14–15 walnut or pecan halves
- 35 peanuts (technically a legume but with a similar nutrient profile to tree nuts).
Raw or sprouted nuts are healthiest. Eat them as they are, or toast in the oven (below 350°F). Dry-roasted nuts are the next best option. Avoid nuts roasted in vegetable or seed oils (e.g., soybean oil) and salted or sugared nuts.
Keep these nutrient-dense morsels at room temp to have grab-and-go foods around. If you’re storing a lot of nuts, refrigerate or freeze to keep fresh.
When Nuts Aren’t Good for You
We’re all biochemically unique, so keep in mind two exceptions to the research indicating that nuts are beneficial for health:
1. If you are allergic to one or more kinds of nuts, you shouldn’t eat them. Eating your specific food allergens is dangerous to your health.
2. If you are a compulsive eater or binge-eater who starts to munch on nuts and can’t stop, avoid eating nuts until you reach a maintenance stage of treating this condition and nuts no longer trigger overeating.
In either of these cases, seeds can sometimes be good substitutes for nuts. Seeds—other than perhaps sesame seeds—generally do not cause allergic reactions as much as nuts do. Also, some people who binge on nuts are not triggered in the same way to overeat seeds.