Eat onions and garlic for your health

This article was originally published in November 2014

Onions, garlic, shallots, chives and leeks make up the allium family of vegetables, which provides great flavor and nutrition to cuisines all around the world. Alliums rarely are eaten alone; instead, their unique flavors are most often combined with other vegetables and spices, as they seem to make everything taste better.

Antioxidant onions

Choosing the most colorful vegetables helps us boost our intake of antioxidants, but onions are a notable exception to this rule. Onions are the richest dietary source of quercetin — one of the most researched antioxidants. Also found in apples and tea, quercetin has demonstrated some pretty impressive anticancer properties (in the lab). Its anti-inflammatory properties also make it heart healthy, and its natural antihistamine properties make it useful for seasonal allergies and asthma. While all onions are rich sources of quercetin and other antioxidants, red onions contain the most, followed by yellow and then white varieties (so that colorful vegetable rule still is useful!).

Immune-boosting garlic

Garlic pills are one of the most common supplements used for heart health — and research supports using garlic to improve blood pressure, blood cholesterol and blood flow, and to reduce inflammation. Garlic also is one of the most potent foods to support our immune system. Garlic’s antibacterial properties help fight off the bacteria that often make us sick, while garlic’s unique sulfur compounds support our body’s internal immune and detoxification systems.

Additional benefits

The health benefits of garlic, onions, and their allium brethren have been recognized throughout history — ancient Egyptians recognized the antitumor properties of garlic in 1500 B.C. In addition to having detoxification effects, alliums also are believed to be useful as aphrodisiacs; as a result, monks, yogis and practitioners of Ayurvedic medicine avoid them.

How to maximize flavor (and nutrition)

When garlic is finely minced, an enzyme (allinase) found in raw garlic comes into contact with the phytonutrient alliin and converts it to allicin, the most bioactive form of this particular nutrient. To maximize this effect for optimal nutrition, allow garlic to aerate for 5 to 10 minutes after chopping it and prior to cooking. This step also will mellow the flavor of the garlic (so you can eat more of it!). This approach works for other alliums as well.

The antioxidants in onions and alliums are stable with cooking, which is good because many people prefer onions and garlic cooked rather than raw. Many of the antioxidants in onions seem to concentrate in the outer levels of onions, so don’t peel off too many layers when prepping your onions.

Did you know?

The sulfur-like flavors found in allium vegetables help to keep pests away on the farm. As a result, alliums often end up on the “Clean 15” list because they are less likely to be sprayed with pesticides.

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