Cancer is increasingly affecting younger people, causing growing concern. However, according to a Korean doctor with more than 15 years of experience, prevention can begin right at the dinner table. He highlighted five familiar food groups that may help strengthen the immune system and support cancer prevention.

After many years of treating cancer patients, Dr. Nam Sang-geun of South Korea believes that daily eating habits can make a significant difference to overall health.

According to him, choosing the right foods not only boosts immunity but may also help reduce the risk of cancer cell formation and growth.

Dr. Nam is a breast and thyroid surgeon who previously worked at the Breast Cancer Center of Yonsei University’s Severance Hospital. With over 15 years of experience, he frequently shares health-care knowledge on his personal YouTube channel.

According to the specialist, the following five food groups should be included regularly in the diet to help protect the body.

Tomatoes and Garlic
Tomatoes contain lycopene — the antioxidant responsible for their bright red color — which helps protect cells from free radicals. Garlic, meanwhile, is rich in allicin, a compound believed to help inhibit the growth of abnormal cells.

To support health, the doctor suggests eating 1–2 medium-sized tomatoes along with 2–3 cloves of garlic daily as part of a balanced diet.

Cruciferous Vegetables
Vegetables such as broccoli, cauliflower, and cabbage are highly valued because they contain sulforaphane, a plant compound that may help suppress the growth of abnormal cells.

Dr. Nam recommends consuming around 100–200 grams of cruciferous vegetables each day. For broccoli, steaming or lightly blanching is considered the best cooking method to preserve nutrients that can be lost at high temperatures.

Fermented Foods
Kimchi, fermented soybean paste, and other probiotic-rich foods are considered “helpers” for the digestive system. These foods help balance gut microbiota, support immunity, and reduce inflammation in the body.

According to Dr. Nam, maintaining a daily habit of eating fermented foods in moderate amounts may help strengthen the body’s natural defenses.

Soybeans and Soy Products
Soy foods are familiar to many people. Tofu, soy milk, and soybeans provide high-quality plant protein while also containing healthy fats and fiber.

In particular, isoflavones found in soy are believed to help prevent the growth of cancer cells. However, the expert cautions against overconsumption. According to Chosun, people should limit intake to about half a block of tofu or one cup of unsweetened soy milk per day.

Omega-3 Rich Plant Oils
Dr. Nam encourages the use of perilla oil or flaxseed oil instead of repeatedly reheated cooking oils.

According to him, plant oils rich in Omega-3 help maintain cellular function, support metabolism, and reduce oxidative stress — a factor associated with many chronic diseases, including cancer.

In addition, doctors emphasize that a healthy lifestyle — including regular exercise, adequate sleep, sensible sun exposure, balanced nutrition, routine health checkups, and avoiding stimulants — is an important “shield” against cancer risk.

For people who have undergone cancer treatment, building healthy habits and maintaining a positive, optimistic mindset not only helps the body recover better but may also improve quality of life and extend longevity.