Can antioxidants really fight cancer? Are free radicals really harmful?

Many health care products under the banner of “antioxidation” like to focus on exaggerating the harm of free radicals to human body, advocating statements like “free radicals can damage DNA, accelerate cell aging, and may also lead to cancer, heart disease, etc.”

These businesses hail antioxidants as [the gospel of mankind in the 21st century]. It seems that by supplementing antioxidants, people can resist aging and avoid diseases such as cancer. But can antioxidants really fight cancer? Do free radicals really do great harm? Are antioxidants really safe?

Is antioxidant what?

Most antioxidants come from natural foods and synthetic products. Among them, we are most familiar with vitamin C and vitamin E, as well as various carotenoids, such as-carotene, lycopene, anthocyanin, astaxanthin, lutein, etc., and selenium.

There are many kinds of health products in this family, and all kinds of health products with strange names promoted by most businesses are indeed antioxidants.

Chemically speaking, antioxidants are a kind of substances that prevent oxidative reactions. Laboratory studies have shown that oxidative stress caused by free radicals can damage cells, and antioxidants can slow down or prevent this damage, and oxidative stress is related to many diseases.

However, it may not be reliable to scavenge free radicals by supplementing additional antioxidants.

Human life activities are complex and relatively stable. Antioxidants sound beautiful, However, a certain balance must be maintained between various antioxidants to be effective. Moreover, being effective in the laboratory cannot be completely equivalent to being effective in the human body. The current findings on the intricate relationship between free radicals and antioxidants are only the tip of the iceberg. There are many complicated life activities involved, and it may not be wise to break the balance maintained by the body without authorization.

Free radicals, is it really harmful?

Health product advertisements will emphasize the harm of free radicals. Is free radicals what?

Free radicals are molecules with strong activity. Some of the free radicals in our body come from outside the body. For example, during smoking, a large number of free radicals of various types enter the respiratory tract. Too strong ultraviolet rays can also produce free radicals and burn the skin. However, the most free radicals in the body are produced by [living gas]-oxygen. With the participation of oxygen, the body’s energy-producing organelles [mitochondria] will convert food molecules into energy available to the body through metabolic processes, which also produce free radicals.

Free radicals are very active and are easily attracted by genetic materials in cells and undergo chemical reactions. A popular hypothesis is that free radicals can damage genetic materials, lead to gene mutations, lead to canceration, and also cause damage to human cells and lead to aging. But as long as the body carries out metabolism, free radicals will be produced. Is our body so stupid?

In fact, mitochondria, while metabolizing, will also wrap themselves up with double-layer membranes to try their best not to let free radicals run into the cells to make trouble. On the other hand, cells have already taken measures to deal with it, either by synthesizing it themselves or by supplementing antioxidants with food to clean up free radicals.

Moreover, in a young and healthy body cell, free radicals are crucial to normal life activities such as energy supply and immunity. For example, the body will use free radicals to attack invading bacteria and even use free radicals to clean up cancerous cells.

Vitamin C is good but not harmful?

Vitamin C is probably the most famous antioxidant. You may have heard that it can fight colds and cancer. The author of this statement is Pauling, winner of the Nobel Prize in chemistry and the Peace Prize.

In 1970, he formally put forward the theory that vitamin C can resist colds, and began to continuously promote this theory. < < Journal of the American Medical Association > > first raised doubts, but Pauling ignored the criticism and began to publicize the protective effect of vitamin C on cancer.

However, subsequent clinical trials by the famous Mayo Clinic in the United States denied the claim that vitamin C can treat cancer [4]. In recent years, other studies have pointed out that vitamin C may interfere with the efficacy of some chemotherapy drugs [5]. The U.S. Food and Drug Administration (FDA) also pointed out that there is no scientific evidence or important research to prove that vitamins have the effect of preventing and treating colds.

Potential risks of antioxidants

In addition to vitamin C, the potential hazards of other antioxidants have gradually become clear with the deepening of research.

Research in the New England Journal of Medicine shows that, Vitamin E and-carotene not only cannot reduce the incidence of lung cancer among smokers, but also greatly increases the incidence of lung cancer [6]. Another large-scale randomized controlled study in the United States obtained similar results: intake of-carotene and vitamin A will increase the incidence of lung cancer and mortality from cardiovascular diseases [7].

In recent years, some authoritative medical journals such as Lancet have published many studies one after another, showing that some antioxidants not only have no protective effect on common cardiovascular diseases and cancers, but also have various unexpected harmful consequences, increasing the risk of disease and mortality [8-10].

Antioxidants, supplement or not?

Pauling’s conceit made all kinds of health care products manufacturers laugh from ear to ear. Until today, all kinds of vitamins and trace element supplements with antioxidant effect are still regarded as [health care products] by the public. However, few people have heard the calls from the medical profession that they are harmful and useless.

The advice in the medical field is: without malnutrition or various chronic diseases caused by lack of vitamins, trace elements, etc., no additional supplements are required at all.

Even if you lack vitamins, you should follow the doctor’s advice to buy vitamins as drugs instead of colorful health products. The former has much higher purity, activity and safety standards than the latter, and the price is approachable. Why spend money to take risks?

Editor: Yidan

Author: Alien Rookie