On the Benefits of Colds

November 13, 2019

Colds and Cancer

I recently came across a fascinating medical article online, which prompted me to write about the benefits of catching a cold and how to make use of one.

In Seitai, the “benefits” of catching a cold have been discussed for around 60 years. The founder of Seitai gave lectures on the subject in the 1960s, and these lectures were compiled into a book entitled COLDS AND THEIR BENEFITS, published in 1986. My teacher, Kuniaki Imoto, also published a book in 1995 entitled Catch a Cold! Develop a Fever!

You may be wondering what on earth we mean by this. A cold is an illness: you may have to take time off work, and the symptoms can be unpleasant.

In Seitai, however, a cold is viewed as the body’s ultimate refreshment — a spontaneous series of reactions that resets the body to a healthy, well-balanced state.

More specifically, in children, this may include an increase in vocabulary, traditionally described in Japan as “wisdom fever”, as well as growth in height and a more toned body. In adults, the skin may become more supple, the complexion may improve, the body may become more flexible, and the normal body temperature may rise, among other changes.

There have even been some observations, although they are relatively rare, of cancer disappearing or serious illnesses improving after a fever caused by a cold or influenza.

It may sound like pseudoscience, but a recent scientific article entitled “Bouts of fever may make us more resilient to cancer” also states that:

“For decades, numerous studies have suggested a link between a history of fever and a lower risk of cancer.”

It also reports that scientists have found that fever caused by infection can markedly increase Vγ9Vδ2 T cells, which may account for up to 60% of white blood cells in the blood, and increase gamma-delta T cells, potentially playing a key role in developing long-lasting immune resistance to tumours.

As you may know, many of what are referred to as “intractable diseases” are thought to be related to abnormalities in immune function.

Fever caused by infection is an important part of the immune system’s response. Therefore, when you take an antipyretic, the immune system’s natural response is interfered with. From the perspective of traditional Seitai, this is regarded as one of the major factors that can contribute to abnormalities in immune function.

So, if you want to restore or strengthen your immune function, the next time you catch a cold, I recommend allowing it to run its course as naturally as possible, without interfering with it unnecessarily.

Here is how.

How to Make Use of a Cold

1. Do not take cold medicine. Avoid solid food.

Cold medicines are intended to suppress the various symptoms of a cold, but many of these symptoms are actually the result of normal immune and elimination responses. Suppressing them therefore also means suppressing the body’s immune response and its ability to eliminate unwanted substances.

Substances that are not eliminated may accumulate in the body and potentially contribute to other illnesses later in life.

The reason for avoiding solid food is that eating activates the process of absorption, which interferes with the body’s elimination process.

Before absorption, there is digestion. Just as eating too much can leave you feeling unable to move, using energy for digestion takes energy away from metabolism. This puts the brakes on the increased metabolism that should occur when the body develops a fever during a cold. As a result, the fever may smoulder and the cold may last longer, with a cough tending to linger.

By avoiding solid food and reducing both the amount and nutritional load of what you consume — in other words, keeping the stomach as empty as possible — the course of a cold can become dramatically shorter and the symptoms milder.

For fluids, drink sports drinks, consommé soup, tea, and so on according to what your body seems to ask for.

(In many parts of the world, people traditionally drink alcohol such as vodka when they have a cold in order to induce sweating. In Seitai, however, we advise avoiding alcohol because it is thought to stiffen the liver.)

2. Keep moving as normally as possible.

This may also seem contrary to common sense, but when you have a fever, the body is considered to be in a state of jitsu — a “switch-on” state. As long as you follow Point 1, you may find that you can carry on moving surprisingly normally. Moreover, movement further stimulates metabolism.

You may have heard stories of athletes competing while running a high fever and achieving unexpectedly good results.

However, “as normally as possible” does not mean pushing yourself. Do not overdo it.

3. Stimulate the back of the head with a hot towel.

If the fever has started naturally, there is no need to do this. However, if you do not develop a fever, have a prolonged low-grade fever, or your temperature repeatedly rises and falls without progressing properly, placing a hot towel on the back of the head (at the base of the skull) is said to stimulate the brain’s fever-regulating centre and encourage a normal fever response.

After about five minutes, the towel will become lukewarm, so heat it again and repeat the process around three to five times in total. The fluctuations in temperature provide the most effective stimulation.

4. If you feel like taking a bath, take one.

In the past, many Japanese homes had their bath outside the main house, and people could become chilled by the outdoor air after bathing. This is one reason people were traditionally told not to take a bath when they had a cold.

Today, however, with indoor bathrooms being standard, warming the body enough to feel comfortable and sweat a little can make the course of a cold much easier.

There is no need to take a bath if you feel too tired or simply do not want to. Follow what your body is asking for.

5. After the fever goes down, rest and avoid solid food for around 16 hours.

When the fever goes down, the body enters the opposite state: an exhausted kyo — a “switch-off” state. This is referred to as a “low-temperature phase”, during which your body temperature may be slightly below your normal level when measured.

If you eat as though you need to “make up” for the nutrients you have lost during this period, the liver may become swollen and take a long time to return to normal.

Also, if you subject your body to strong stimulation or allow it to become chilled during this period, the cold may return and can then tend to linger.

Summary

If you follow these points, the course of a cold should become dramatically shorter. In Seitai, it is said that having a cold for two days is already “too long”.

The ideal way to have a cold is like a child: developing a high fever all at once, yet surprisingly still having enough energy to play; suddenly losing interest in food, going to sleep, and waking up the next day as if nothing had happened.

If you allow a cold to run its course successfully, the fever and elimination processes increase metabolic activity. You may then notice that your complexion has improved, your skin looks clearer, your body feels more toned, or that long-standing discomfort or pain has disappeared.

What is said in Seitai is often the complete opposite of conventional wisdom, but these approaches have been tested through long years of practical experience. And, as mentioned earlier, some aspects of these traditional observations have subsequently found support in Western medicine.

Update in 2026

More than six years have passed since I wrote this article, so I asked AI to check the latest information. Research into gamma-delta T cells has progressed considerably, and the current understanding appears to be that:

1. Blood cancers: The most promising area, partly because these cancers are more accessible to immune cells and easier for them to recognise.

2. Solid cancers: There is some potential, but effectiveness depends on specific conditions.

3. Conditions for effectiveness: Tumour infiltration, a low-immunosuppressive environment, and the appropriate subtype appear to be key factors.

4. Direction of development: Combination therapies are becoming the main focus rather than gamma-delta T cells being used as a stand-alone treatment.

5. Practical assessment: Promising for blood cancers, but more limited for solid cancers.

6. The underlying role: Rather than directly attacking tumours, their role may be more closely related to broader activation of the immune system.

Of course, Seitai is based on practical experience rather than scientific evidence, and there is no established clinical evidence demonstrating that the approach described in this article can treat or prevent cancer or other diseases. Please do not neglect standard medical care or rely on fever as a treatment.

Always give priority to the advice of your doctor or other qualified healthcare professional. Please regard the ideas described here simply as a reference to one perspective found in a traditional Japanese practice with around a century of accumulated experience.