Everyone has a different requirement for water. Temperature, humidity, size, age, gender and activity have an influence on your fluid needs.

Instead, drink when you are thirsty.

Sugar does not seem to have any hyperactive effect on children.

This myth was popularized with the Feingold Diet in the 1970s, where parents were advised to remove sugar to help calm their children.

The word "detox" is used as an advertising buzzword.

Fifteen products that claim to detoxify, were reviewed by scientists. When the investigators inquired what toxins were targeted and how these toxins were removed, the companies were unable to provide answers.

• A chain email in the 1990s was responsible for the false belief that antiperspirant was raising the risk of breast cancer. 
• When researchers found higher ratios of aluminum in the brains of Alzheimer's patients, aluminum in antiperspirant was suspect. But it seems aluminum in antiper...

It does not matter when you eat. Your body treats a calorie like a calorie, regardless of when it was ingested.

Vaccines can cause side effects that may have potential problems for some children.

The upside is that it may provide protection from diseases like polio, measles or whooping cough.

Eggs have a lot of cholesterol compared to other foods. Although cholesterol in the blood is strongly related to heart disease, eating cholesterol is weakly associated with raising the cholesterol levels in your blood.

Eggs have other heart-protecting properties and eating it ...

Your brain is active regardless of what activity you do. Some parts of the brain are used fro certain activities more than others, but there aren't areas that aren't used.

Your immune system is a complex series of processes involving antibodies, certain proteins, parts of your blood, and more.

When a product claims to boost your immune system but does not specify which part of the immune system, you should question it.

(For example, activatin...

Swimming right after eating does not give you cramps.

If you do cramp while you swim, tighten and relax the muscle until the cramp works its way out.

Colds do not come from going outside with wet clothes or hair. Colds come from viruses and may spread at any time.

Colds and flu spread easier in winter because people are spending their time together in close proximity.

Cracking knuckles can cause swollen hands and loss of some grip strength. The popping noise comes from bubbles bursting in your joint fluid. It, however, does not cause arthiritis.

Disease-causing microbes are everywhere, not just in public toilets. However, toilets are cleaned more often. Compared to other objects like keyboards, cellphones or money, the toilet is not a major source of disease-carrying microbes.

A diet book was released in 1996 claiming that diets depended on a person's GBO genotype, but a large study involving 1455 people debunked the theory.

Most bacteria we come into contact with are either neutral or beneficial to us.

However, there are harmful bacteria that can cause diseases like tuberculosis or cholera.

Antibiotics are prescribed only for bacterial infections. It is futile against viruses.

The color of your mucus does not indicate a bacterial infection. Viruses can produce a green mucus, too.

Eating fruit, vegetables and whole grains are healthier than eating processed foods. 

However, food with organic or natural ingredients can be full of saturated fat, sugar or other empty calories that can make it a less healthy choice.

Radiation can be either high-energy or low-energy. High-energy radiation like x-rays and gamma rays can damage your DNA.

Low-energy radiation from smartphones or microwaves is not strong enough to damage DNA.