Superfood Avocado: How the Green Fruit Improves Your Health
Avocados not only taste delicious, they also offer a number of health benefits, that is the reason why they are considered a superfood. In fact, the green fruit is high in fiber, unsaturated fats, especially monounsaturated fats (healthy fats), and other beneficial components, such as minerals and vitamins, that are associated with good health. The heart, intestines, metabolism and cells benefit from the superfood. A 30-year study of more than 110,000 healthcare professionals found that participants who ate at least two servings of avocado per week had a lower risk of cardiovascular disease than those who ate the food less frequently. 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, researchers followed more than 68,780 women (aged 30 to 55 years) from the Nurses’ Health Study and more than 41,700 men (aged 40 to 75 years) from the Health Professionals Follow-up Study. All study participants were cancer, coronary heart disease, and stroke free at baseline and resided in the United States. Researchers documented 9,185 cases of coronary heart disease and 5,290 strokes during more than 30 years of follow-up. Researchers assessed participants’ diets using food frequency questionnaires given at baseline and every four years thereafter. They calculated avocado intake using a questionnaire that asked about the amount consumed and frequency. A serving was equal 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% reduced risk of cardiovascular disease and a 21% reduced risk of coronary artery disease compared to those who never or only rarely reached for the fruit.
Based on statistical models, replacing half a serving of margarine, butter, egg, yogurt, cheese, or processed meats like bacon with the same amount of avocado every day was associated with a 16% to 22% reduced risk of cardiovascular disease. Previous research has shown that eating an avocado a day can help to 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. Studies found that avocados helped to reduce oxidized LDL particles. Much research suggests that oxidation is the basis of diseases such as cancer and heart disease. When LDL particles are oxidized, a chain reaction is set off, promoting atherosclerosis.
Avocado Promotes a Healthy Gut
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 individuals who ate avocado every day had greater numbers of gut microbes, which break down fiber and produce metabolites that in turn support gut health. They also had greater microbial diversity compared to those who did not consume this food. Microbial metabolites are compounds that microbes produce 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 received one meal per day as a substitute for breakfast, lunch, or dinner. One group ate an avocado with each meal, while the control group ate a similar meal but without the avocado. Participants provided blood, urine, and stool samples throughout the 12-week study. They also reported how much they consumed from the meals provided, and every four weeks they recorded everything they ate. While other research on avocado consumption has focused on weight loss, participants in this study were not advised to limit or change their diet. Instead, they ate their normal diet, except that they substituted one meal per day for the meal provided by the researchers.
The researchers found that while the avocado group ate slightly more calories than the control group, they excreted slightly more fat in their stool. Greater fat elimination means the research participants absorbed less energy from the foods they ate. This was likely due to the reduction in bile acids, molecules that our digestive system secretes that allow us to absorb fat. It was found that the amount of bile acids in the stool was lower and the percentage 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 have a positive effect on the intestinal microbiota.
Losing Weight With Avocado
Avocados also have the potential to promote healthy weight loss and the reduction of belly fat. Research has shown that an avocado a day can help redistribute belly fat towards a healthier profile in women. 105 overweight and obese adults participated in a randomized, controlled study that included one meal a day for 12 weeks. Women who consumed avocado as part of their daily meal had a reduction in deeper 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 internal organs. Individuals with a higher percentage of visceral fat tend to have a higher risk of developing diabetes. Therefore, the researchers were interested to determine whether the ratio of subcutaneous to visceral fat changed when 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 no 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 of diabetes. Female participants who consumed an avocado daily as part of their meal saw a reduction in abdominal visceral fat — the hard-to-reach fat associated with higher risk — and a reduction in the ratio of visceral fat to subcutaneous fat, suggesting redistribution of fat away from the 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 losing weight, as studies have shown that they support a healthy feeling of fullness and reduce the craving for overeating. The healthy fats and fiber in the fruit stabilize blood sugar levels while the body is slowly and steadily 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 their body cannot properly remove glucose from the blood. These complications can occur when mitochondria, or the powerhouses in the body’s cells, are unable to completely 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. Over the next five weeks, they added AvoB to half the mice’s high-fat diets. The treated mice weighed significantly less than the control group and showed slower weight gain. More importantly, the treated mice showed higher insulin sensitivity, meaning their bodies were able to absorb and burn blood sugar and improve the response to insulin.
In a human clinical trial, AvoB administered as a dietary supplement to participants following a typical Western diet was safely absorbed into the blood without affecting the kidneys, liver, or skeletal muscles. The team also saw weight reduction in human subjects.
Avocado in the Fight Against Cancer
Studies have long linked fruit and vegetable consumption to a reduced risk of various types of cancer in humans. The protective effect is attributed to the high levels of phytonutrients, or phytochemicals – plant compounds believed to have health-protecting properties – that are often found in dark-colored fruits and vegetables. Researchers from the University of Ohio found that Hass avocado extracts kill or stop the growth of precancerous cells that lead to oral cancer. Hass avocados are a perennial fruit known for their characteristic bumpy skin that turns from green to purplish-black as it ripens. The prostate can also benefit. Some research suggests that avocado extract inhibits prostate cancer cell growth. These studies suggest that single and a combination of phytochemicals from the avocado fruit may offer a beneficial nutritional strategy in cancer prevention.