Onions and garlic belong to the Allium family, which also includes leeks, chives, scallions, and shallots. They are rich in odoriferous sulfur compounds including thiosulfinates, sulfides, and sulfoxides.

Onions (Allium cepa) are very rich in fructo-oligosaccharides which stimulate the growth of healthy bifidobacteria and suppress the growth of potentially harmful bacteria in the colon. They can reduce the risk of tumors developing in the colon.

Garlic (Allium sativum L.) is a rich source of two classes of organosulfur compounds: (1) gamma-glutamylcysteines and (2) cysteine sulfoxides. Approximately 80% of the cysteine sulfoxides in garlic is allylcysteine sulfoxide (allin), the organic compound allicin, which gives garlic its aroma and flavor, and acts as the world’s most powerful antioxidant. Modern science has shown that garlic is a powerful natural broad-spectrum antibiotic.

Health Benefits of Onions

Lowers Blood Sugar

Onions contain allyl-propyl-disulphide which lowers blood sugar levels by increasing the amount of free insulin available for delivering glucose into cells. Onions are also a good source of chromium, the mineral component in glucose, a molecule that helps the appropriate insulin response in cells.

Chromium can lower blood glucose levels, improve glucose tolerance, lower insulin levels, decrease cholesterol and triglyceride levels, while increasing HDL- cholesterol (good cholesterol) levels in diabetics, clinical studies have shown.

Chromium levels are depleted by the consumption of refined sugars and white flour products as well as the lack of exercise. One cup of raw onion contains over 20% of the Daily Value for chromium, an important trace mineral.

Good for the Heart

Studies have shown that regular consumption of onions has been shown to lower high cholesterol levels, lower high blood pressure, prevent atherosclerosis, prevent diabetic heart disease, and reduce the risk of heart attack or stroke.

Scientific studies of more than 100,00 individuals who included onions, tea, apples and broccoli, the richest sources of flavonoids, gained a 20% reduction in their risk of heart disease.

Good for the Colon and Gastrointestinal Health

According to  research published in Clinical Gasteroenterology and Hepatology, onions contain quercitin, an antioxidant, and curcumin, a phytonutrient found in tumeric, that may reduce both the size and number of precancerous lesions in the intestinal tract.

Cancer Prevention

Case control studies from Southern European populations, as reported in the American Journal of Clinical Nutrition, indicate that making onion, as well as garlic, a staple in your diet may greatly lower your risk of several common cancers.

The participants in these studies consuming the most onions showed: 84% reduced risk of cancer of the oral cavity and pharynx; 88% reduced risk for esophageal cancer; 56% reduced risk for colorectal cancer; 83% reduced risk for laryngeal cancer; 25% reduced risk for breast cancer; 73% reduced risk for ovarian cancer; 71% reduced risk for prostate cancer; and, 38% reduced risk for renal cell cancer, compared to those eating the least amount of onion.

Studies in Greece, China, and central Georgia (Vidalia onion country) have shown a high consumption of onions, garlic, and other allium herbs to be protective against stomach cancer.

Shopping for Onions

Western Yellow onion, New York Bold onion, and Northern Red onion are the richest in flavonoids and phenolics (hydrocarbon with antiseptic & disinfectant properties), giving them the greatest antioxidant and anti-proliferative activity of 10 onions tested. The mild-tasting Western White and Vidalia onions had the lowest antioxidant content and lowest anti-proliferative activity. The onions with the strongest astringency have the superior health promoting properties.

Good for Bone Health

Onions contain a compound named gamma-L-glutamyl-trans-S-1-proopenyl-L-cysteine sulfoxide, or GPCS for short. This newly found compound inhibits the cells (osteoclasts) that break down bone. This may be especially beneficial for women, who are at risk for osteoporosis as they enter menopause. GPCS works in a similar manner as Fosamax (Alendronate) without the potential negative and dangerous side effects attributed to the drugs. The onions protect bones in a natural and positive manner.

A Natural Anti-Inflammatory and Anti-Bacterial

Besides vitamin C and quercitin, onions contain the anti-inflammatory component isothiocyanates that inhibits lipoxygenase and cyclooxygenase, the enzymes that cause inflamatory conditions such as pain and swelling of osteo and rheumatoid arthiritis, asthma, and the respitorycongestion associated with the common cold. Quercitin and other flavonoids found in onions work along with vitamin C to help kill harmful bacteria. Good idea to use onions in soups and stews during cold and flu season.

Health Benefits of Garlic

Garlic has a long history in medicine, in the form of a syrup and as a poultice for bronchitis. A native to southern Europe garlic, from Spain to Greece, has been a cooking staple for thousands of years. In the 19th century, Louis Pasteur, the famous French chemist, demonstrated garlic’s antiseptic properties, a discovery that aided the armies of Britain, Germany, and Russia, during both World War I and II.

Helps Lower Blood Pressure and High Cholesterol

Major studies indicate that allicin, a chemical formed when garlic is crushed or chopped, reduces cholesterol levels and lowers high blood pressure. Garlic also reduces the ability of blood platelets to form clots, thereby reducing the risk of heart attacks or stroke. The organosulfur compounds in garlic have been found to inhibit the activity of inflammatory enzymes, which appear to play a role in the pathology of heart disease.

May Prevent Some Cancers

The antioxidant properties of garlic, like onions, reduces the risk of cancer of the colon and esophagus, and may aid in shrinking cancers of the breast, skin, and lungs. Allicin and SAC (S-allyl-cystein) have been successful against tumors in lab animals.The sulfur compounds in garlic drive out carcinogens before they can damage cell DNA and force cancer cells that do develop to self-destruct.

Antibacterial and Antifungal Properties

Garlic extracts have been found to have antibacterial and antifungal properties. Thiosulfinates, particularly allicin, a potent antimicrobial, can fight off bacteria, viruses, and fungi. Studies in Britain have shown that those who ingest raw garlic for 12 weeks during cold season were far less likely to get sick than those who took placebos. Of the garlic takers who did catch a cold recovery was four days sooner on average than the others. Just one clove of garlic a day gives you the needed vitamins of A, B, and C, as well as minerals including selenium, iodine, potassium, iron, calcium, zinc and magnesium. Two cloves, or more, a day may protect you from the flu or help you recover faster if you get the flu or the common cold.

Studies conducted at the University of California irvine Medical Center suggest that garlic is a powerful antibiotic. Garlic juice demonstrates significant antibacterial activity against a spectrum of pathogens including antibiotic-resistant strains such as methicillin-resistant and ciprofloxacin-resistant staphylococci, vancomycin-resistant enterococci, and ciprofloxacin-resistant Pseudomonas aeruginosa. A second study found that garlic also inhibits methiicillin-resistant Staphylococcus aureus (MSRA). MSRA is the antibiotic-resistant bacteria found in hospitals.

(By adding chopped garlic to your socks and wearing the socks in bed while you sleep at night, has been shown to kill athlete’s foot).

In Summary

For optimal health and prevention of disease include onions and garlic in your daily diet, preferably in their raw state. Add onions to your salads, sandwiches, stews, etc. Even cooked they will provide some benefit. Garlic juice can be added to salad dressings or add sliced-up garlic into salad mix. If you eat garlic by itself also eat some parsley, as the chlorophyll will take away any bad breath. Garlic cloves added to meat dishes enhance savory flavors. Use you imagination, experiment. Garlic and onions are natural remedies as well as natural seasonings. Enjoy.