Garlic and onions are commonly used as ingredients to add flavor to foods; they are also known for improving health as they contain many natural antioxidants, such as polyphenols.
In a study published in the Journal of Dietary Supplements, garlic, white onion, and purple onion were proven to exhibit powerful antioxidant activities which are helpful in lowering blood pressure and preventing Type 2 diabetes. In particular, they were found to inhibit key enzymes linked with Type 2 diabetes and hypertension.
For the study, a team of researchers from the Federal University of Technology in Nigeria looked at the inhibitory effect of aqueous extracts of garlic, white onion, and purple onion on key enzymes linked with Type 2 diabetes and hypertension, such as angiotensin-converting enzyme (ACE), alpha-amylase, and alpha-glucosidase activity in vitro. In addition, the research team assessed the extracts’ antioxidant properties through different antioxidant assays.
The results of the study revealed that the aqueous extracts of garlic, purple onion, and white onion all displayed inhibitory activities against ACE, alpha-amylase, and alpha-glucosidase activity in a dose-dependent manner. When it comes to inhibiting ACE, purple onion extract exhibited the highest inhibitory effect among the three. However, white onion exhibited the greatest inhibitory effect on alpha-amylase among the three extracts.
Based on the results of the antioxidant assays, the aqueous extracts of garlic, purple onion, and white onion also exhibited free radical-scavenging activity and prevented lipid peroxidation in the pancreas and heart.
With these findings, the researchers concluded that garlic, white onion, and purple onion can help prevent high blood pressure and diabetes because of their inhibitory effect on key enzymes linked with diabetes and hypertension and their powerful antioxidant properties.
More reasons to eat garlic and onions
Both garlic and onion belong to the allium family of vegetables. The sulfur compounds that give them their pungent smell and taste are the same substances that are responsible for their health benefits. In addition to preventing hypertension and Type 2 diabetes, garlic and onions:
- Fight infections: Garlic and onions help fight infections. According to a study published in the journal Phytotherapy Research, onion can fight harmful bacteria and might improve the symptoms of bronchitis and the common cold. On the other hand, garlic possesses both antibacterial and antifungal properties and strengthens the immune system, which lowers your risk of contracting infections.
- Ward off cancer: Eating garlic and onions can also help lower your risk of cancer. Research has shown that onion and garlic can prevent cancer. Their cancer-fighting properties can be attributed to their chemical compounds that can slow down or inhibit cancer cell growth and development in various parts in the body, such as the breasts, colon, esophagus, and lungs. According to the Linus Pauling Institute, garlic may be particularly effective against gastric and colorectal cancer.
- Prevent heart disease: You can also protect your heart against heart disease by eating garlic and onions. Onions are loaded with flavonoids, which are natural chemicals that can prevent heart diseases. Onions can also lower your risk of blood clots, which can result in heart attacks and other forms of cardiovascular disease. On the other hand, garlic helps keep the arteries flexible and lowers your blood pressure. Like onions, garlic also lowers the risk of blood clots.
- Fight obesity: The oils in garlic and onions can counteract the effects of a high-fat diet, which helps you maintain a healthy weight and prevent weight-related diseases, according to a study published in the journal Nutrition and Metabolism.
Ways to eat garlic and onions
Nutrition experts suggest that eating garlic and onion in their raw forms is the best way to reap their benefits. Prepare garlic and onions by chopping or crushing them five to 15 minutes before eating. This will trigger them to release their chemical components and enable them to mix and form new phytonutrients. You can add them raw to your salads, sandwiches, soups, sauces and dips, and cooked dishes.