Let's go nuts

Nutritionally, nuts have a lot to offer, and they should figure more in our diets — and not just as snacks.

Nuts are dense little packages of fat and protein, with most of the fat being the healthful, unsaturated kind. They don't contribute much in the way of vitamins but make up for it by supplying respectable amounts of potassium, magnesium, and several other required minerals.

Dieters have tended to stay away from nuts because the fat content makes them a high-calorie food. It doesn't help that we tend to shovel them in as snacks, not as part of meals. But nuts contain very little carbohydrate, so they're showing up in low-carb diets these days, particularly the ones that emphasize plant-based foods.

A couple of studies have found a correlation between relatively high nut consumption (two or more servings a week) and avoidance of weight gain and obesity. Researchers at Harvard-affiliated Beth Israel Deaconess Medical Center reported results from a small (20 volunteers) study that showed walnuts at breakfast gave people a pre-lunch feeling of fullness that might make it easier to eat less. Ultimately, weight loss is about reining in calorie consumption (and increasing physical activity). But if nuts make people feel full, perhaps they can help lower calorie counts over all, even as they add to those totals.

Apart from weight issues, nuts seem to have some protective effects against heart disease. Numerous studies have shown that if you put people on nut-filled diets, favorable effects on cholesterol levels, blood pressure readings, and inflammatory factors follow. And in large epidemiologic studies, high nut consumption has been associated with lower rates of heart disease. An analysis of data from the Harvard-based Nurses' Health Study showed that having one serving of nuts a day is associated with a 30% lower risk of heart disease compared with having one serving of red meat a day. A plate full of walnuts for dinner tonight? That's not very appealing. But cookbooks are full of recipes that incorporate nuts into pasta dishes and the like. And it would be easy for most of us to add almonds or walnuts to a bowl of cereal or low-fat yogurt at breakfast and occasionally eat a meatless lunch or dinner.

Nuts may help with diabetes, too. The lack of carbohydrate content means nuts don't add appreciably to the surges in blood sugar we experience after many meals. In fact, they can blunt the effects of carbohydrates on blood sugar levels. Those "postprandial" spikes in blood sugar contribute to the development of diabetes in people vulnerable to getting the disease and must be controlled in those who have already have it. Yet the evidence for nut consumption reducing the risk for developing diabetes is mixed, as are results of studies of the effect it has on blood sugar levels.