Will using the air conditioner overnight cause facial paralysis? Is sleeping on a hard bed better for the waist? Here comes the August science rumor list →

1. Is sleeping on a hard bed better for your waist?

Rumor: A hard bed is better for maintaining the angle of the spine and making the waist healthier.

Truth interpretation: This is not the case. The normal human spine has an "S"-shaped physiological curve. Sleeping in a supine position on a hard bed will cause the waist to be suspended in the air. In the long run, it may cause tension and soreness in the waist muscles, and even stiffness and strain of the spine. Studies have shown that a medium-hard mattress is the first choice, which can better support the spine and reduce muscle burden. When choosing a mattress, you should consider factors such as your age, gender, body shape, and habitual sleeping position to ensure that the mattress can evenly support the body and maintain the natural curvature of the spine. In addition, a suitable sleeping position and daily core stability training are also very important for maintaining waist health. Therefore, when choosing a mattress, you should pay attention to its rationality and comfort in supporting the human body, rather than simply pursuing too hard or too soft.

Source: Science Refutes Rumors

2. Can exercising in extreme weather improve physical fitness?

Rumor content: In bad weather conditions, insisting on exercising can stimulate your potential and enhance your physical fitness.

Truth interpretation: Exercising in extreme weather does not enhance physical fitness. Outdoor exercise during the "dog days" is prone to dehydration and heatstroke, so "summer exercise during the dog days" should not be recommended. If you must exercise, it is recommended to do it indoors with air conditioning, or outdoors in the evening/night when it is cooler, and to replenish water every 15 minutes during exercise to prevent heatstroke. The same is true for the "nine days". Cold weather can easily induce cardiovascular and cerebrovascular diseases. Coupled with the high incidence of haze in winter, emphasizing outdoor exercise at this time is counterproductive. In addition, this type of exercise is not suitable for the elderly. The cardiopulmonary function and adaptability to exercise of the elderly are very different from those of young people. Going out in excessively cold or hot weather is already a big test, not to mention exercise.

Source: Tencent

3. Is it because of the injection of hormones that the Enoki mushrooms “reverse their growth” in the refrigerator?

Rumor content: Enoki mushrooms are "reversely grown" when placed in the refrigerator due to excessive use of hormones by unscrupulous merchants.

Truth: Not true. It is normal for Enoki mushrooms to grow in a refrigerator, and it has little to do with whether plant hormones are used. The formation of Enoki mushroom fruiting bodies requires a lower temperature, about 6-10°C is more suitable. The refrigerator has a suitable temperature, humidity and light-proof environment, and the culture medium remaining in the roots of Enoki mushrooms provides nutrients, which creates good conditions for the growth of Enoki mushrooms during cold storage. It is not surprising that the so-called "reverse growth" occurs.

Source: Tencent

4. Will using the air conditioner all night cause facial paralysis?

Rumor content: Many people like to sleep with the air conditioner on during hot weather. Some people find their faces are paralyzed after getting up in the morning and think it is caused by the air conditioner and fan at night.

Truth Interpretation: This statement lacks basis. Facial paralysis is a common disease, but the cause is still unknown. Although a small number of imprecise studies have suggested that cold stimulation may be related to facial paralysis, based on existing research evidence, authoritative medical organizations and institutions do not accept the statement that air conditioning, electric fans or cold wind are one of the causes when explaining the causes of facial paralysis. Therefore, it can be said that the current evidence does not support that air conditioning or fans will cause facial paralysis. If the cold wind is uncomfortable on your head, you can consider adjusting the wind direction or installing a baffle.

Source: Tencent

5. If you have kidney stones, do you no longer need to supplement calcium?

Rumor: Kidney stones contain a lot of calcium. If you take calcium supplements when you have kidney stones, the condition will get worse.

Truth: Quite the opposite. Having kidney stones does not mean that calcium supplementation is completely impossible. In fact, proper calcium supplementation is necessary for patients with kidney stones and can help reduce the risk of stone formation. Kidney stones are mainly composed of calcium oxalate. Proper calcium supplementation can reduce the body's absorption of oxalic acid, thereby reducing the risk of calcium oxalate stones. A low-calcium diet may cause excess oxalate to enter the blood, increasing the risk of urinary stones. Therefore, patients with kidney stones should take reasonable calcium supplements according to the doctor's advice, and pay attention to drinking more water and doing outdoor activities to promote the synthesis of vitamin D and help calcium absorption.

Source: Science Refutes Rumors

6. Does excessive foam when urinating indicate kidney problems?

Rumor: Urine conditions can reflect physical health; more foam means decreased kidney function

Truth interpretation: Foamy urine does not necessarily mean that there is a problem with the kidneys. In most cases, it may be caused by harmless factors in daily life, such as a high-protein diet, high urine concentration, fast urine flow rate, or intense contact with the toilet water surface when urinating while standing. These factors can cause the air in the urine to be entrained into the liquid, forming foam. At the same time, normal urine contains solutes with similar surfactant properties, such as urea, mucin, phospholipids, etc., which are in very low levels and can only maintain bubbles for a short time. However, if foamy urine lasts for a long time and the amount of foam is large, especially when accompanied by other symptoms such as edema, fatigue, changes in urine color or decreased urine volume, this may be a warning sign of kidney disease. In these cases, it is necessary to seek medical attention in time for relevant examinations.

Source: Science Refutes Rumors

About the Science Rumors List

Released by the China Association for Science and Technology, the list is reviewed by experts every month. Based on criteria such as timeliness and harmfulness, hot rumors are selected for special interpretation and pushed across the entire network.

Jointly published: Scientific rumor-busting platform, China Internet Joint Rumor-busting Platform, "Study to Strengthen the Country" learning platform

Supported platforms: Weibo rumor refutation, Toutiao rumor refutation, Tencent Jiuzhen, NetEase Health, Toutiao Health, Baidu Knows, Douyin

Scientific rumor debunking: Sponsored by the China Association for Science and Technology, the National Health Commission, the Ministry of Emergency Management, the State Administration for Market Regulation and other ministries and commissions, guided by the Central Cyberspace Affairs Commission, and jointly created by national societies, authoritative media, social organizations and scientific and technological workers, it aims to effectively improve the dissemination, guidance and influence of rumor debunking information, so that rumors can stop at the wise and let science outrun rumors.

List of review experts (in order of the number of strokes of surnames)

Ma Yong, Professor of Wuhan Institute of Physical Education

Ruan Guangfeng, Deputy Director of Kexin Food and Health Information Exchange Center

Wang Qian, Chief Physician of the Emergency Department, the Third Medical Center, PLA General Hospital

Chen Rui, Associate Professor, Institute of Communication Psychology, School of Journalism, Communication University of China

Tang Qin Director of the Science Popularization Department of the Chinese Medical Association National Health Science Popularization Expert

This article is produced by "Science Facts" (ID: Science_Facts). Please indicate the source when reprinting.