Nuts for health

Do you eat nuts?

Although nuts are calorically dense and contain a high amount of fat, I eat some nuts every day, and we include them in our kids’ lunchbox.

Last week a new study in the Archives of Internal Medicine gave further evidence to support this tasty habit.

In this study, part of the large PREDIMED (Prevención con Dieta Mediterránea) Spanish study, the researchers compared the one-year effect of two types of Mediterranean diets—one enriched with virgin olive oil (one liter per week of virgin olive oil) and the other enriched with nuts (30 grams, or about an ounce per day, of mixed nuts—walnuts, hazelnuts and almonds) with a low fat diet on symptoms of metabolic syndrome.

The metabolic syndrome is a constellation of unhealthy attributes--abdominal obesity, high blood fats, elevated blood pressure, and high blood glucose—which are well-documented risk factors for cardiovascular disease. It is well known that dietary pattern has a great influence on the incidence of the metabolic syndrome, and that the Western diet in particular promotes this syndrome, while traditional diets rich in fruits, vegetables and grains lower the risk.

It’s also well known that, for overweight people, losing extra weight has a good chance of reversing the metabolic syndrome.

But can just improving the diet, without losing weight achieve the same result?

I find this study so interesting because the participants in the intervention groups actually increased the (unsaturated) fat content of their diet, were not instructed to limit caloric intake or increase exercise, showed a strong commitment to the intervention (as it was quite easy and tasty), but nevertheless achieved significant health benefits.

Here’s what this study of 1,224 men (aged 55-80) and women (aged 60-80) showed:

• At the start of the study 751 (more than 60 percent) of the participants had symptoms of metabolic syndrome. This was a high-risk group.

• The researchers randomized the participants to one of three groups: Mediterranean diet plus virgin olive oil group, Mediterranean diet plus nuts group, and a low-fat diet group, which acted as the control.

• The Mediterranean diet groups received quarterly education about the Mediterranean diet which encouraged increased consumption of fruits, vegetables, fish, olive oil, white meat vs. red meat, aromatic herbs, and moderate consumption of wine. The low-fat diet group was given advice on low-fat diets.

• At the end of one year, the metabolic syndrome rate went down by 13.7 percent in the Mediterranean diet plus nuts group, 6.7 percent in the Mediterranean diet plus olive oil group, and 2 percent in the low fat diet (control) group.

• Statistical analysis shows that the metabolic syndrome, present at the beginning of the study, reverted in Mediterranean diet plus nuts group.

• Although there was no significant change in body weight (patients did not lose weight), and overall the two groups assigned the Mediterranean diet increased their intake of total fat and total energy (calories), the metabolic status of these group members improved.

The researchers conclude:

“Traditionally, dietary patterns recommended for health have been low-fat, high-carbohydrate diets, which generally are not palatable. The results of the present study show that a non–energy-restricted traditional MedDiet (Mediterranean diet) enriched with nuts, which is high in fat, high in unsaturated fat, and palatable, is a useful tool in managing the MetS (metabolic syndrome). Dietary intervention may reduce cardiovascular risk among persons with the MetS”

One can only guess what the accumulated effect of improving diet components (eating a more Mediterranean diet) combined with exercise and weight loss could achieve. As we all know, losing weight and keeping a commitment to exercise are not easy tasks, whereas eating more of something tasty is quite doable for most people.

So, what’s so good about nuts?

Nuts are a whole food, rich in protein, fiber, arginine, vitamin E, magnesium, copper, phosphorus, potassium, calcium, selenium and folate.

The fats in nuts are mostly unsaturated fats, especially monounsaturated fat, which lower low-density lipoproteins (LDL or “bad” cholesterol) and increase high-density lipoproteins (HDL, the “good” cholesterol). Nuts contain the essential fatty acids. One ounce of walnuts meets the daily recommendation for omega-3 fatty acids. Nut consumption has been associated with lower risk of cardiovascular disease in several good studies.

An average handful equals about one ounce of nuts. One should remember that an ounce of nuts contains 160-200 calories (depending on nut type), so don’t overdo it if you’re watching your weight. But, nuts are quite filling and several studies show that weight gain was not a problem when subjects were fed nuts within the context of a balanced diet.

It’s very easy to add nuts to your life. You can eat them as a snack; sprinkle them on salad, yogurt, pasta and cereal; add them to batters, stews and stir fried dishes—the options are endless.

You can read more about the connection between food and the metabolic syndrome in my post here.

Enjoy your nuts. In moderation though.
Ayala