Welcome to Straight Talk on Health. I’m your host Dr. Chet Zelasko. Straight Talk on Health is a joint production with WGVU in Grand Rapids MI. I examine the practical application of health information. Nutrition. Exercise. Diet. Supplementation. I look at the science behind them, and let you know whether it’s something to consider or not. You can check out other things that I do on my website Drchet.com and sign up for my free emails.
“Like buttah.” That’s the phrase I think of every time I think of avocados. It increases at this time of the year because that’s when the avocado growers chose to advertise at sporting events. I’ve developed a taste for avocados over the past 20 years. I’m glad I did because this is one nutrition powerhouse. Let’s take a look at avocados in general and then the results of a recent study.
The avocado is actually the fruit of an evergreen tree. Avocados are native to Central and South America but today, they are cultivated in California and Florida within the US and anywhere that’s hot and humid enough to grow them. The advantage for us is that they are available in your grocery store all year round. There are dozens of varieties of avocadoes but the Hass variety is the most popular type of avocado in the United States.
Avocados are technically fruits just like tomatoes but because they are more savory, they are traditionally used as vegetables in preparing meals. The perceived problem with avocadoes is that they are high in fat. Fat is still considered the enemy in many diet approaches but maybe the nutritional profile will change that thinking. Let’s take a look.
The first thing that jumps out is the fat content – 20-30 g of fat in about 4 ounces of avocado, depending on the type. But looking at the type of fat in the avocado, only 3 g are saturated. The bulk of the fat – 21 g – is monounsaturated fat. That’s the same healthy fat that’s found in olive oil. And before you ask “is avocado oil a good fat to use in salads and cooking” the answer is yes as it has a good smoke point. The second thing that make avocadoes special is the fiber content at 9 g of fiber in 4 ounces of avocado. When you consider that our fiber intake averages just 12-13 g per day, avocadoes can add to significant amount to our fiber intake.
Let’s turn to the vitamin and mineral profile. If we set 20% of the Daily Value as a criteria, then the nutrients that exceed that value include Vitamin C, vitamin K,
vitamin B6, folate, pantothenic acid, magnesium and potassium. Any way you look at it, the nutrient profile of the avocado great.
While the vitamin E content wasn’t over 20% in the avocado, the high-fat content could enable vitamin E and other fat-soluble vitamins to be absorbed from other foods eaten in a meal. Why? In order to absorb fat soluble vitamins like beta carotene, A, D, K as well as E, fat has to be present. This is an example of the role that quality fats play in our nutritional health. We can reduce the saturated fat from fried foods and vegetable oil but we need quality fats for important reasons such as this.
The final part of the avocado worth mentioning are the phytonutrients and it has many types. The first group is called phytosterols, Phytosterols are plant-derived compounds that are similar in structure and function to cholesterol. Research demonstrates that phytosterols may help prevent the absorption of cholesterol. That can benefit our overall heart health.
Avocadoes are also high in carotenoid antioxidants,. We tend to think about carotenoids as concentrated in bright orange or red vegetables like carrots or tomatoes. While those vegetables are great sources of carotenoids, avocado—despite its dark green skin and largely greenish inner pulp—also contains a significant variety of carotenoids.
The third group are non-carotenoid antioxidants, including the flavonoids epicatechin and epigallocatechin 3-0-gallate (EGCG), vitamins C and E, and the minerals manganese, selenium, and zinc.
The final group are omega-3 fatty acids, in the form of alpha-linolenic acid, and polyhydroxylated fatty alcohols (PSA)s. Both of these have demonstrated anti-inflammatory tendencies in test tube studies. It remains to be seen if that will carry over to human studies. Bottom line: the avocado is a super power when it comes to nutrition.
How do you pick a good avocado? I’m no expert but from what I’ve learned, you want a fruit with no visible dents or blemishes, not too soft unless you plan on using it the same day. I tend to get avocadoes that are firm but do respond to pressure. If I know I’m going to eat avocadoes in a day or two, I buy them hard and leave the to ripen on the counter. If they get to the ripened stage I like, I put them in the fridge. The thing is, you can’t buy avocadoes weeks in advance because they do ripen and start to lose nutritional value. The California Avocado Commission has plenty of videos on the best way to peel avocados in order to retain all those nutrients I mentioned earlier. Use your search engine to find them.
So, how are you going to eat your avocadoes? I cut them up and put them on salads and slice them to use in sandwiches. I also make a dip—not really a salsa—by slicing them up, adding an herb-based sea salt, and them mash them until they get a lumpy yet smooth texture. But there is another way I enjoy them: using the mashed avocado spread as a substitute for mayonnaise instead of slicing them like I said earlier. When you consider that mayonnaise has 100 calories per T, using even 2 T of avocado spread lowers the calories to just 50 calories and gets you all those phytonutrients and higher quality fat.
Let’s take a look at a recently published study in the AJCN that illustrated the potential benefits of substituting 300 calories from fat in the diet with 300 calories from avocado. Researchers recruited subjects with elevated fasting triglycerides—greater than 135 mg/dl up to 499 mg/dl. The subjects were also overweight or obese but otherwise healthy. They screened over 150 potential subjects and 42 met the criteria with an average age of 50 years. For three weeks, on a random basis, subjects ate either a prepared normal American diet with 40% fat from traditional sources like meats and oils or a diet prepared with 300 calories from avocado while removing 300 calories from fat. After a two week washout period, the subjects ate the opposite diet and the data from each diet were pooled for analysis.
The results showed a decrease in all serum lipid values but a significant 10% decrease in fasting triglycerides—an average of 17 mg/dl when eating the avocado substituted diet. In just three weeks. They put avocados in foods a person wouldn’t expect like muffins as well as salsas and salad dressings and used natural food dyes in the regular version to mask the color of the avocado.
Two important points. The diets were precise in substituting 300 calories of fat with 300 calories from avocado. They just didn’t add avocado to an already high fat diet. We don’t really know whether it was the type of fat in the avocado, the high fiber content, or some other nutrients that elicited the effect on TG; we just know that avocados were substituted in innovative ways. Second, this isn’t the be all and end all study on food substitutions. But it does show that dietary changes need to be consistent to be effective. Whatever strategy you use to eat healthier, you have to be consistent to get results.
That’s all the time I have for this episode. If you like this podcast, please hit the share button and tell your friends and colleagues about it. Until next time, this is Dr. Chet Zelasko saying health is a choice. Choose wisely today and every day.
Reference: https://doi.org/10.1016/j.ajcnut.2025.101137
