Cancer was the leading cause of death in Hong Kong. Research indicated that individuals who consumed the highest amounts of allium vegetables significantly reduced their risk of various cancers.

Dr. Chang Shih-heng shared on his YouTube channel that allium vegetables belonged to the Amaryllidaceae which including a strong smell but were rich in various organic sulfur compounds that could inhibit cancer cells, while they also contained abundant phytochemicals such as quercetin and flavonoids at the same time.

Chang also listed the eating recommendations for the Onions, Garlic, Green Onion and leeks which can reduce the risk in Stomach cancer, Head and neck cancer, Esophageal cancer, Colorectal cancer, Lung cancer, Prostate cancer and Breast cancer.

1. Onions

Nutritional Benefits:

Rich in glucoraphanin, onions would turn into sulforaphane after being chopped, which could inhibit cancer cells.
Rich in quercetin: This compound influenced RNA segments in the body, preventing harmful genes from affecting normal cells.
Containing a variety of organic sulfides, such as DMS, DADS, DATS, DTTS and DPDS, which could damage the DNA of cancer cells and stop the growth of these cells.
Studies have found the DADS sulfide contained could neutralize certain carcinogens in cigarettes and remove nitrosamines in processed meats that can cause colorectal cancer.

Eating recommendations:

Consider eating raw onions to make full use of the sulfide in onions to prevent cancer.
Leave the diced onions for 10 minutes before adding them to cooked vegetables or lettuce salad. The spicy taste would be reduced and the sulfide could also be preserved intact.
Using low-temperature cooking to optimize quercetin intake, the best method is to fry the onions at 160°C for 4 to 8 minutes without allowing them to turn brown.

2. Garlic

Nutritional Benefits:

Contains the most important active ingredient "allicin", which was a sulfide.

Eating recommendations:

Take about 10 grams (about two cloves) of garlic per day.
In order to fully release allicin, It is recommended to chop the garlic and let it sit for at least 10 minutes to allow the fully release of allicin
Since allicin is a sulfide, it is best to eat it raw.

3. Green onions

Nutritional Benefits:

Rich in organic sulfides, phytochemicals and trace elements.
It should be noted that the green part of the upper half of the green onion and the white part of the white onion have different characteristics, given the smell of the white onion is stronger with most of the sulfides concentrated,it is often used to remove the fishy smell.
Green onions contained higher density of phytochemicals, vitamins and minerals, such as carotenoids, folic acid, vitamins A, B, C, E, K, calcium, selenium, magnesium and iron

Eating recommendations:

Eating raw can preserve the most sulfides.
Stir-fry at low temperature quickly can break the cell wall and release these substances to take in the most polyphenols

4. Leeks

Nutritional Benefits:

A study in 2016 showed women who consumed lots of leeks could significantly reduce their breast cancer risk by 70 percent, a higher reduction than garlic.

Eating recommendations:

Leeks planted in an environment with insufficient light would grow yellow leeks, which were softer, tenderer and sweeter than green leeks. It is best to choose fresh green leeks that are exposed to sufficient light during the growth process to obtain a higher nutrition density.

How to remove residual smell of onion and garlic?

Consume foods that could neutralize sulfide molecules, such as lemon, coriander, milk and apples.
Drink a cup of tea, coffee or apple cider vinegar.
Eat Chew gum
Massage the salivary glands near the jaw or temporomandibular joint to increase saliva secretion and allow the protein in the saliva to carry away the sulfide.

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