Nutritional powerhouse

The avocado tree, Persea americana, is native to Mexico and central America, and grows well in tropical and subtropical climates around the world, including Florida and California. Many people avoid avocados because of their high fat content, but about 70% of their fat is a type called monounsaturated. A diet high in monounsaturated fat has been linked to reduced cardiovascular risk in multiple controlled trials in people with type 2 diabetes. Monounsaturated fats feature prominently in the Mediterranean-style diet, which diabetes experts recognize as one that can help improve blood sugar regulation and protect against heart disease.

One thorough review analyzed the combined findings from nine controlled intervention trials, which included a total of 1,547 adults with type 2 diabetes or impaired glucose tolerance. The analysis showed that, compared with diets low in monounsaturated fats, having more of these fats in the diet improves glucose control. The study authors concluded that diets with plenty of monounsaturated fats may be part of an effective strategy for reducing hemoglobin A1c (HbA1c)—lower HbA1c indicates better glucose control—and therefore should be recommended as part of a type 2 diabetes nutrition plan.

What's in an avocado?

While the recommended serving size may be smaller than many of us expect, 1/5 of a medium avocado has a lot to offer. For example, per serving, avocado provides 4 milligrams of vitamin C, 195 milligrams of potassium, plus 2.7 grams of fiber. Avocados are also very low in sugar. Further, avocados have a low glycemic index, which means they don’t raise blood sugar levels as quickly as some other foods, such as refined carbohydrates.

Adding avocados

Although they offer many benefits, remember to eat avocados in moderation since the calories do add up. For most people, 1/5 of a medium avocado, which has about 50 calories, is a reasonable serving and can replace a serving of another fat source like butter or mayonnaise.

(Ann Nutr Metab 2011;58:290–96)