Avocados not only taste delicious, they also offer a range of health benefits, which is why they are rightly counted among the superfoods. In fact, the green fruit contains plenty of fiber, unsaturated fats, especially monounsaturated fats (healthy fats) and other beneficial components such as minerals and vitamins that go hand in hand with good health. The heart, intestines, metabolism and cells all benefit from superfoods. A 30-year study of more than 110,000 health professionals found that participants who ate at least two portions of avocado per week had a lower risk of cardiovascular disease than those who ate less often. Replacing animal products such as butter, cheese or bacon with avocado was also associated with a lower risk of cardiovascular disease. The results were published in the Journal of the American Heart Association.
Avocados reduce the risk of heart disease and counteract bad cholesterol
For 30 years, the researchers followed more than 68,780 women (aged 30 to 55) from the Nurses’ Health Study and more than 41,700 men (aged 40 to 75) from the Health Professionals Follow-up Study. All study participants were free of cancer, coronary heart disease and stroke at the start of the study and lived in the United States. The researchers documented 9,185 cases of coronary heart disease and 5,290 strokes during more than 30 years of follow-up. The researchers assessed the participants’ diets using food frequency questionnaires administered at the beginning of the study and then every four years. They calculated avocado intake using a questionnaire that asked about the amount and frequency consumed. One serving was equivalent to half an avocado or half a cup of avocado. After accounting for a wide range of cardiovascular risk factors and general diet, study participants who ate at least two servings of avocado each week had a 16% lower risk of cardiovascular disease and a 21% lower risk of coronary heart disease compared to those who never or rarely consumed the fruit.
Based on statistical models, replacing half a portion of margarine, butter, egg, yogurt, cheese or processed meat such as bacon with the same amount of avocado each day was associated with a 16% to 22% lower risk of cardiovascular disease. Previous research has already shown that eating one avocado a day can help keep ‘bad cholesterol’ in check. According to the researchers, bad cholesterol can refer to both oxidized low-density lipoprotein (LDL) and small, dense LDL particles. In studies, avocados were found to help reduce oxidized LDL particles. Much research suggests that oxidation is the basis for diseases such as cancer and heart disease. When LDL particles are oxidized, a chain reaction is triggered, promoting atherosclerosis.
Healthy gut thanks to avocado
Eating avocado as part of your daily diet can also improve your gut health, according to studies from the University of Illinois. The researchers found that people who ate avocado every day had a greater number of gut microbes that break down fiber and produce metabolites that in turn support gut health. They also had a greater microbial diversity compared to people who did not eat this food. Microbial metabolites are compounds produced by the microbes that affect health. Avocado consumption reduced bile acids and increased short-chain fatty acids. These changes correlate with beneficial health outcomes.
The study included 163 adults between the ages of 25 and 45 who were overweight or obese – defined as a BMI of at least 25 kg/m2 – but otherwise healthy. They were given one meal a day to replace breakfast, lunch or dinner. One group ate an avocado with each meal, while the control group ate a similar meal but without avocado. Participants provided blood, urine and stool samples during the 12-week study. They also reported how much they consumed of the meals provided, and every four weeks they recorded everything they ate. While other research on avocado consumption has focused on weight loss, the participants in this study were not advised to restrict or change their diet. Instead, they ate their normal diet, with the exception that they replaced one meal a day with the meal provided by the researchers.
The researchers found that while the avocado group consumed slightly more calories than the control group, slightly more fat was excreted in their stool. Greater fat excretion means that the research participants absorbed less energy from the food they ate. This was probably due to a reduction in bile acids, molecules secreted by our digestive system that allow us to absorb fat. It was found that the amount of bile acids in the stool was lower and the amount of fat in the stool was higher in the avocado group. Different types of fat have different effects on the microbiome. They were thus able to prove that the valuable fats and fiber in the avocado had a positive effect on the intestinal microbiota.
Lose weight with avocado
Avocados also have the potential to promote healthy weight loss and the reduction of abdominal fat. Research has shown that one avocado a day can help redistribute belly fat towards a healthier profile in women. 105 adults with overweight and obesity participated in a randomized controlled trial that included one meal a day for 12 weeks. Women who consumed avocado as part of their daily meal had a reduction in deep visceral abdominal fat.
There are two types of fat in the abdomen: fat that accumulates just under the skin, called subcutaneous fat, and fat that accumulates deeper in the abdomen, known as visceral fat, which surrounds the internal organs. People with higher levels of visceral fat tend to have a higher risk of developing diabetes. Therefore, the researchers were interested in determining whether the ratio of subcutaneous to visceral fat changed as a result of eating avocado.
The participants were divided into two groups. One group received meals with a fresh avocado, while the other received a meal with almost identical ingredients and similar calories, but without avocado. At the beginning and end of the 12 weeks, the researchers measured the participants’ abdominal fat and their glucose tolerance, a measure of metabolism and a marker for diabetes. Female participants who consumed an avocado a day as part of their meal saw a reduction in visceral abdominal fat – the hard-to-reach fat associated with higher risk – and a reduction in the ratio of visceral fat to subcutaneous fat, indicating a redistribution of fat away from organs. However, fat distribution in men did not change, and neither men nor women showed improvements in glucose tolerance.
In general, avocados are recommended when it comes to weight loss, as studies have shown that they support a healthy feeling of satiety and reduce cravings for overeating. The healthy fats and fibre in the fruit stabilize blood sugar levels, while the body is slowly and evenly supplied with energy.
How avocado helps with diabetes
Researchers at the University of Guelph have shown that a compound found only in avocados can inhibit cellular processes in the pancreas that normally lead to diabetes. Diabetics suffer from insulin resistance, which means that their bodies cannot properly remove glucose from the blood. These complications can occur when mitochondria, or the energy power plants in the body’s cells, are unable to fully burn fatty acids. Normally, fatty acid oxidation allows the body to burn fats. Obesity or diabetes hinder this process and lead to incomplete oxidation.
The U of G researchers discovered that avocatin B (AvoB), a fat molecule found only in avocados, counteracts incomplete oxidation in skeletal muscle and the pancreas to reduce insulin resistance. In their study, the team fed mice a high-fat diet for eight weeks to induce obesity and insulin resistance. For the next five weeks, they added AvoB to the high-fat diet of half of the mice. The treated mice weighed significantly less than those in the control group and showed slower weight gain. More importantly, the treated mice showed higher insulin sensitivity, meaning that their bodies were able to absorb and burn blood sugar and improve the response to insulin.
In a human clinical trial, AvoB given as a dietary supplement to participants on a typical Western diet was safely absorbed into the blood without affecting the kidneys, liver or skeletal muscles. The team also saw a reduction in weight in human volunteers
Avocado in the fight against cancer
Studies have long linked the consumption of fruits and vegetables to a reduced risk of various cancers in humans. The protective effect is attributed to the high levels of phytonutrients or phytochemicals – plant compounds thought to have health-protective properties – often found in dark-colored fruits and vegetables. Researchers at Ohio State University found that extracts from Hass avocados kill or stop the growth of precancerous cells that lead to oral cancer. Hass avocados are perennial fruits known for their characteristic bumpy skin, which turns from green to purplish-black as they ripen. The prostate may also benefit. Some research suggests that avocado extract inhib its the cell growth of prostate cancer cells. These studies suggest that individual and a combination of phytochemicals from the avocado fruit may offer a beneficial nutritional strategy in cancer prevention.