Last month, we explored the fascinating Designer Foods Program, launched by the U.S. National Cancer Institute in the early 1990s. Researchers investigated ordinary foods containing naturally occurring compounds that might help reduce the risk of cancer.
One of the most interesting foods highlighted in the famous Designer Foods Pyramid was garlic, a member of the Allium family.
This month, I would like to introduce you to the rest of this wonderful family, particularly one of the most affordable and versatile vegetables we can find in almost any grocery store: the onion.
Meet the Allium Family
You probably eat members of this family almost every day without giving them much thought.
Onions - yellow, white, red, and sweet onions
Garlic
Leeks
Scallions (green onions)
Chives
Shallots
These vegetables have something special in common: their distinctive aroma and flavour come partly from naturally occurring sulfur-containing compounds.
Have you ever wondered why chopping an onion makes you cry? Or why crushing garlic releases such a powerful aroma?
When we cut, crush, or chew these vegetables, their cells are damaged, allowing enzymes and sulfur-containing substances to react and produce new compounds. These reactions are responsible for much of their characteristic smell, taste, and some of the biological activities that have attracted scientific interest.
What Does Modern Cancer Research Say?
The Allium family became an important subject of research because of its organosulfur compounds.
In laboratory and animal studies, certain compounds from garlic and onions have demonstrated activities relevant to cancer biology, including:
Influencing enzymes involved in processing potentially harmful substances
Affecting inflammation and oxidative stress
Influencing cell growth and programmed cell death
Affecting biological pathways involved in cancer development
However, an important distinction must be made.
Promising laboratory findings do not necessarily mean that eating onions or garlic will prevent cancer in humans.
Human population studies have produced mixed findings, and current evidence does not establish that eating a particular quantity of garlic or onions will prevent cancer.
Nevertheless, these vegetables can be valuable parts of a varied, plant-rich dietary pattern associated with better long-term health.
Onions Have More to Offer
Onions contain another interesting plant compound called quercetin, a flavonoid also found in foods such as apples and certain berries.
Quercetin has been studied for its antioxidant and anti-inflammatory activities. Red and yellow onions are particularly interesting sources, although the amount varies by variety and preparation.
Onions also provide some vitamin C, potassium, and prebiotic fibers that can be fermented by our intestinal bacteria.
So even without calling onions a miracle cancer-preventing food, there are plenty of reasons to enjoy them regularly.
What Does Chinese Medicine Say About Onions and Garlic?
In traditional Chinese dietary therapy, we look beyond the individual nutrients contained in a food.
We consider its nature, flavour, preparation, and how it interacts with the person eating it.
Onions and garlic are generally considered pungent and warming.
The pungent flavour is traditionally associated with dispersing and moving Qi. Warming foods can help support the Middle, particularly when Cold is affecting digestive function.
Garlic (Da Suan, 大蒜) has traditionally been used to warm the Stomach, disperse Cold, and support digestion.
Onions (Yang Cong, 洋葱) are also commonly described in Chinese dietary therapy as pungent and warm, with an ability to promote the movement of Qi.
This is particularly interesting during the cooler months, when we naturally begin to enjoy more warm, cooked meals.
However, more is not always better. Someone experiencing pronounced Heat symptoms or digestive irritation may not benefit from large quantities of raw garlic or onions.
And preparation matters.
A raw onion has a sharp, pungent bite. When slowly cooked, it becomes soft, sweet, and much gentler in flavour. Chinese Medicine encourages us to consider not only what we eat, but also how we prepare it and who is eating it.
Healthy Food Doesn’t Have to Be Expensive
Once again, I want to return to the central message of this series.
We don’t need expensive powders, exotic superfoods, or a cupboard full of supplements to begin improving our everyday diet.
Sometimes the most useful ingredients are already sitting in our kitchen.
An onion may cost very little, yet it can bring flavour, fibre, and a variety of naturally occurring plant compoundsto our meals.
And rather than eating enormous quantities of one particular vegetable, we can combine different foods throughout the week.
Onions today. Cabbage tomorrow. Daikon another day.
Variety matters. And the changing seasons can help guide that variety.
Try It This Week
If you’ve been looking for a simple way to put this month’s teaching on your plate, I’ve paired this blog with a recipe for Japanese-Style Onion Steak with Garlic Butter, a dish that features two members of the Allium family and transforms a very ordinary onion into the star of the meal.
[Read “A Pantry Powerhouse: Japanese-Style Onion Steak”]
Or feel free to text 519-781-6957 or email info@trilliumchinesemedicine.com with any questions.
Next month: we’ll continue the series with another humble, affordable, often-overlooked everyday food.