Avocado Health Benefits
As described earlier in our “What’s New and Beneficial” section, U.S. adults who consume avocado average some important nutrient benefits, including intake of more potassium, vitamin K, vitamin E, fiber, magnesium, and monounsaturated fat. In addition, they average greater overall intake of fruits and vegetables and have better overall diet quality. Due to their higher calorie content, avocados do not rank as high in our rating system as do other nutrient-rich foods with fewer calories. However, there are very few DRI vitamins or minerals not found in avocado! In this food you will find all B vitamins except vitamin B12; vitamin C (at 20% of our WHFoods recommended daily level in one cup); phosphorus, manganese, and copper at more than 10% of our WHFoods recommendation); and 8% of our recommended daily omega-3s.
In addition to these conventional nutrients, avocados offer a wide range of phytonutrients that are related to their unusual fat quality. Included in this category are the phytosterols (beta-sitosterol, campesterol, and stigmasterol) as well as their polyhydroxylated alcohols. The major carotenoid found in the pulp of avocado is chrysanthemaxanthin. Other carotenoids in the pulp include neoxanthin, transneoxanthin, neochrome, and several forms of lutein. As mentioned earlier, avocado is also an especially rich source of monounsaturated fatty acids, and in particular, oleic acid, which accounts for over 60% of the total fat found in this food.
It would be wrong to conclude this nutritional support section without mentioning the improved absorption of carotenoids that can take place when very low-fat, carotenoid-rich food might otherwise be consumed in the absence of fat. As described earlier in our What’s New and Beneficial section, many of our best foods for obtaining carotenoids—for example, sweet potatoes, carrots, and leafy greens—contain very little fat (less than 1 gram per serving). This absence of fat works against their absorption into the body, and the addition of a fat-containing food like avocado can change this situation pretty dramatically. Anywhere from two to six times as much absorption of carotenoids has been found to occur in these very low-fat, high carotenoid dietary situations. In addition, the combination of carotenoid-rich, very low-fat foods like carrots with a high-fat food like avocado has been shown to improve conversion of specific carotenoids (most importantly, beta-carotene) into active vitamin A. We think about this avocado health benefit as another component of its broad-based nutritional support.
Cardiovascular Support Provided by Avocados
Numerous studies have looked at the relationship between avocado consumption and blood fat levels, types of fat in the bloodstream, inflammatory risk in the cardiovascular system, and degree of cardiovascular protection against oxygen-based damage. The study results are consistent in showing benefits from avocado in all of these areas. Most of the benefits are associated with avocado consumption at least multiple times per week in amounts of approximately one cup. (Depending on the variety, one cup of avocado is approximately the same as the amount of pulp found in one small-to-medium sized avocado. Some studies also show benefits with smaller amounts of avocado in the 1/2-cup range.
A wide range of nutrients in avocado has been associated with these cardiovascular benefits. Included in this list would be: (1) avocado fats, which include very large amounts of the monounsaturated fatty acid, oleic acid, as well as the unusual phytosterols, including beta-sitosterol, campesterol, and stigmasterol; (2) the antioxidant nutrients in avocado, including carotenoids like chrysanthemaxanthin, neoxanthin, and lutein as well as vitamin E and vitamin C; (3) anti-inflammatory components of avocado, including the carotenoids and phytosterols listed above as well as catechins and procyanidins (two families of flavonoids).
Risk of metabolic syndrome—which includes symptoms involving problematic blood fat levels and elevated blood pressure—has been shown to be reduced by intake of avocado. Many of the nutrients provided by avocado are likely to play a role in this important health benefit. Research in this area encourages us to think about avocado as being truly preventive in its cardiovascular health benefits, and worthy of consideration in many types of meal plans.
One important note about the cardiovascular benefits of avocado: most of the encouraging studies that we have seen do not simply “dump” avocado into a meal plan as some type of “add-on” food. Instead, avocado is integrated into a balanced diet with a controlled amount of fat, calories, and intake across food groups. There does not appear to be any requirement for the diet to be low fat, since avocado-containing meal plans that provide up to 34% of their total calories from fat have been shown to provide cardiovascular support. But treatment of avocado as an “add-on” food is not an approach that we have seen supported by large-scale research in this cardiovascular area.
Other Health Benefits of Avocados
We believe that avocado is likely to provide you with health benefits in the areas of blood sugar control, insulin regulation, satiety and weight management, and decreased overall risk of unwanted inflammation. However, we would still like to see further expansion of research findings in these areas. With respect to blood sugar and insulin regulation, we have seen smaller scale studies showing reduced insulin secretion after a meal and improved regulation of blood sugar levels, but most of these studies have focused on the short-term situation following a meal rather than extended blood sugar regulation over weeks or months. Some of these studies have focused on the fiber content of avocado, which is more substantial than many people might think. (There are 10 grams of fiber in our one cup website serving.) Also investigated in this area has been the 7-carbon sugar called mannoheptulose (and its polyol form called perseitol). This sugar—unlike most sugars—may help suppress insulin secretion.
In the area of satiety and weight management, we’ve seen studies showing improved feelings of fullness and satisfaction after eating a meal that contained avocado, as well as decreased body mass index (BMI) and total body fat after six weeks of consuming a meal plan that contained 1.3 cups of avocado per day. However, we would also immediately note that participants in this study were required to follow a balanced meal plan with a restricted number of calories (about 1,700 calories per day). So we suspect that avocado can indeed be helpful to include in a weight management plan, but only if the overall plan is well thought out and takes the overall amount of food intake into consideration.
Avocado has clearly been shown to provide a wide variety of antioxidant and anti-inflammatory nutrients. Included here are both conventional nutrients like manganese, vitamin C, and vitamin E, as well as phytonutrients like unique carotenoids, flavonoids, and phytosterols. Most of the larger scale, human research studies that we have seen focus on the cardiovascular system and risk of oxidative stress and inflammation in this system. In terms of the whole body, however, and its many key physiological systems, the antioxidant and anti-inflammatory benefits of avocado have been tested primarily in the lab or in animal studies. For example, numerous animal studies have looked at the impact of avocado intake on risk of inflammation in connective tissue and have speculated about the potential benefits of avocado for reducing human arthritis risk. Because of the promising nature of these preliminary studies, we look forward to new research involving large numbers of human participants and intake of avocado in a weekly meal plan.