Does yoga help eliminate toxins and relieve anxiety [7 myths]

Yoga emerged as a philosophical movement in India, but over time it has become much more: it is a fitness trend, a therapy option, and a way of self-development that more than 30 million people around the world engage in.

But not everything others say about yoga is to be believed. We've compiled the most common claims about the practice and found out how close to the truth they are.

What myths we checked out

- Over centuries of history, yoga has been studied up and down

- All types of yoga work the same way

- Yoga is suitable for absolutely everyone.

- We should not expect yoga to have healing effects.

- Some asanas detoxify and speed up the metabolism.

- Upside-down postures are not allowed during your period.

- Yoga cannot improve your body form.

Over centuries of history, yoga has been studied up and down

In fact the first serious study on the effects of yoga on health was published in 1975, and it involved only 34 people. And that study showed that yoga helps to lower blood pressure. But they were testing on people who already had hypertension, so it's not clear whether yoga helps to support blood pressure in healthy people in the long run.

Since then, scientists' interest in yoga has been growing: they are trying to find out how effective the regular practice is for various diseases and whether it helps to quit smoking, for example. A search of PubMed's scientific article database for the query yoga yields 877 studies.

The gold standard of medical research is randomized, double-blind, placebo-controlled with a large sample. Yoga studies have a problem with this:

- There's no way to do a blind study: in this case, participants don't know whether the treatment they're using is real or placebo. Hiding from participants that they do yoga is not possible;

- there is not always even just a control group that does not do yoga;

- small sample size in most studies - an average of up to 100 people each;

- narrow focus: Researchers study how exercise affects people with certain characteristics or illnesses - hypertension, schizophrenia, depression. There is no certainty that yoga has a preventive effect and will help maintain health;

- there is no data on how yoga changes physical and mental health in the long run.

The good news is that there is more research and the methodology is improving, so maybe we will wait for objective results and find out how yoga works from a biological point of view.

All types of yoga work the same way

That's not true. Any type of yoga consists of a combination of three components: asanas, i.e. postures, pranayama, i.e. breathing practices, and meditation. But each type of yoga mixes them in a different way, and the instructor adds something of his own.

For example, in Ashtanga vinyasa they do a cycle of asanas, including power asanas, practically without any rest breaks - you can get tired after an hour on the mat. Kundalini is more about chanting mantras and breathing, trying to transfer energy to certain chakras. And most of the yoga-nidra class, also called sleep yoga, is lying in shavasana. These are all yoga, but of different intensities and, accordingly, with different effects.

Most researchers do not name specific exercises or even the type of yoga: it is listed only in 150 papers out of 877. Participants in medical research more often do hatha yoga or Iyengar yoga - in 87 and 35 cases, respectively. These are calmer practices consisting mostly of stretching and relaxation poses. Which types work better scientifically is unknown - scientists just haven't compared them yet.

Yoga is suitable for absolutely everyone

No: Like any physical activity, it has limitations. People with hypertension, glaucoma or stroke survivors should be careful with inverted asanas, where the head is below the legs, and downward bends. If there are hernias or protrusions in the spine, instructors advise doing forward bends with straight legs.

Many asanas are excluded during pregnancy: strong bends, twists, jumps, active press exercises, handstands, and handstands on the head are advised to be done only by experienced yogis under the supervision of an instructor.

Even healthy people can get injured because of improper technique. The most common problems occur when doing head or forearm handstands and lotus postures. There has been a case of pneumothorax - an injury in which air enters the chest outside the lung, causing it to contract - after "fire breathing," a rhythmic practice in kundalini yoga. One study found a high risk of meniscus injuries in women who practice yoga for long periods of time.

The first rule of prevention is not to do things that cause pain, or you risk suffering an injury. The second is to practice with a certified instructor.

If you doubt whether yoga is right for you, tell the instructor about your limitations - he or she will explain what you can do and how to do it safely.

This is where the headstand is done by the yoga instructor: she has practiced a lot and understands the risks. I saw another case: a man decided to stand on his hands at a class in the park, but he could not hold on and collapsed on his back. After a 10-minute rest he got up and went home, but it could have ended worse.

Yoga should not be expected to have therapeutic effects

Research says otherwise. Here are a few conditions for which yoga can be beneficial.

Depression. Yoga combined with other therapies can help with symptoms of depression and affective disorder. It cannot be said that specific asanas have this effect. Perhaps the very fact of regular physical activity, meeting new people and belonging to a group has an effect.

In principle, any physical activity makes life easier with depression, although it may be difficult to start exercising for someone in a depressed mood.

Stress and anxiety. Yoga reduces stress and anxiety just as well as other relaxation techniques. That said, stretching exercises themselves probably work even better.

Insomnia. There is evidence that regular practices help women with insomnia fall asleep.

Attention and memory problems. In dementia, regular yoga practice increases concentration and improves verbal memory, that is, the ability to remember verbal information. Researchers attribute this to the fact that participants sleep better and cope with stress.

I would also suggest that this may be due to the need to memorize Indian asana names during practice. Anyway, it is worth noting that studies of the effects of yoga on cognitive function are usually conducted among people who already have noticeable impairments. It is not clear whether the same positive results will be seen in healthy people.

Cardiovascular disease. In hypertensive people who regularly practice yoga, blood pressure is reduced by several points, but only if the exercises are combined with meditation and pranayama - breathing techniques.

Perhaps the reason is that yoga helps to feel one's body better and to control emotions, to pay attention to pain, tiredness and stress. And such people are more careful with themselves: try to eat right, don't overeat, refuse alcohol and smoking, go to bed in time - lead the same healthy lifestyle which is recommended as a part of treatment by cardiologists.

Inflammation. Regular practice of yoga, tai chi or meditation lowers the level of inflammatory markers in the blood. So there is hope that these mindfulness practices can at least alleviate, if not prevent, chronic diseases with which inflammation is associated, such as diabetes or certain cancers.

Back pain. Daily yoga practice reduces the intensity of back pain that is not related to injury or tumor. Scientists can't explain how this works. Perhaps it's the exercise: improved muscle tone, flexibility, joint mobility. Or meditation and a focus on breathing help you pay less attention to pain.

Most researchers haven't compared yoga to other activities, so you can't say it's about asanas or meditation. So if you're exercising for your health, but you're bored in the face-down dog pose waiting for the class to end, you shouldn't force yourself. Try a different kind of yoga or change the activity altogether - any movement is good for your health.

Some asanas detoxify and speed up the metabolism

These claims have no proof. In brief, our kidneys, liver and intestines remove all the waste from our body, and they usually cope with this function without help from the outside.

The idea that twisting promotes the elimination of toxins comes from B. К. S. Iyengar, the founder of one of yoga movements. He thought that during twisting blood does not flow to internal organs, but during relaxation it can flow there, being enriched with oxygen and useful substances. There is no scientific basis for this theory.

The promise that some yoga exercises speed up your metabolism and help you lose weight, studies have not confirmed. On the contrary, due to deep breathing and relaxation, yoga lowers the metabolism, that is, the yogi's body consumes fewer calories.

You can't do inverted positions during your period

Many yoga teachers advise against inverted postures during menstruation: handstands, forearms and even downward facing dog.

In terms of yogic philosophy, this prohibition is explained by the disruption of the movement of life forces. Yogic tradition distinguishes five energy currents, and one of them, apana, runs through the excretory system and sexual organs and is associated with any secretions, including menstrual blood. By this logic, if the uterus is above the head during menstruation, the natural downward movement of the apana is disrupted.

Modern yogis try to explain this prohibition by physiology: supposedly in the inverted positions menstrual blood stagnates in the body and with particles of endometrium gets into abdominal cavity and can provoke endometriosis. This is medically incorrect. Menstruation is a complex hormonal process, which is not affected by body position or gravity, and the discharge is not due to gravity, but to uterine contractions. In space, where there is no gravity at all, women still menstruate and do not suffer from endometriosis.

Yoga can't improve shape

It depends on the type of practice. If you just lie on the mat for the whole class and relax, your muscles won't grow and you're unlikely to become more enduring. But the power asanas are effective. They are especially important for people who can't afford more active exercises because of their health. Judging by one study, six months of regular hatha yoga classes three times a week strengthened the cardiovascular system of elderly people and improved joint mobility.

However, practicing yoga alone is not enough to maintain health. The WHO advises adults to exercise:

- Either moderate aerobic activity for at least 150-300 minutes per week. It can be fast walking at a speed of 5 km/h, dancing, water aerobics, tennis, climbing stairs or washing windows;

- or high-intensity activity of 75-150 minutes. This includes, for example, running more than 9.8 km/h, basketball, fast swimming, jumping rope.

Yoga is not considered an aerobic activity, so it does not replace the recommended 150 minutes of movement. But the WHO has another piece of advice for a healthy lifestyle - two strength training sessions a week for all muscle groups. This is where power yoga asanas, such as the plank, variations of the hero pose, and others are appropriate.