By Elena Voropay

Science of Sweat II - Immunity, Heat and Hormones
Science of Sweat III - How To Stop The Sweat
Can You Smell Ammonia in Your Sweat?
Testing Sweat 
Night Sweats

Everybody sweats, even your pets. There's no escape from it. Your body needs to sweat in order to cool off the internal heat. How much you sweat depends on states of emotion, physical activity, and hormone levels. You have probably noticed that different people not only sweat at different places, but they smell differently too. What is interesting is that sweat itself does not have any smell. So, what is it that your nose is actually detecting? Learn everything about the physiology of sweat and your body.

Burning approximately 2,500 calories a day to fuel all functions of the body, we produce enough heat to bring 25 quarts of water to the boiling point. Exercise generates even more heat. But only about 25 percent of the energy in a workout might be needed for the action of moving, throwing a ball, activating muscles, etc. The other 75 percent is leftover heat released through persiration. The brain's cooling center slows the heating process and opens the glands in the skin to release the excess heat. A pea-sized bead of sweat can cool nearly 1 liter of blood by 1-degree F.

Did you notice that your armpits smell differently than your feet? One of the reasons for that is that these are actually different kinds of sweat made by two types of glands. The body has approximately 2 - 4 million sweat glands weighing about 100 grams. You'll find them just about everywhere on the body, with the exception of the lips, ear, external genitalia, and nail beds. The most concentrated areas of sweat glands are the soles of your feet, while the least concentrated area is on your back.

The odorless sweat on the palms of your hands, soles of your feet and forehead comes from eccrine glands which are the most numerous on the body. This is your 'true sweat' which is secreted straight onto the skin surface, does not have any smell, and consists of 99 percent water, some salts, vitamin C, protective antibodies, toxins and metabolic wastes. Being quite small, less than 0.4 mm in diameter, the number of eccrine glands can be extremely concentrated. Histologists estimate that a single square centimeter of skin on the palms of the hands contains about 450 sweat glands!

Remember your teenage years when you first noticed that some smooth areas of your body become fussy with soft hairs? This is exactly when your apocrine sweat glands came to existence. Armpits and anal-genital area release lipid- and protein-containing sweat along with water and other basic substances of true sweat giving you the 'distictive' smell. Being quite viscous with milky or yellowish color, this type of perspiration is liberated into the hair follicles.

When you become too psyched up before your workout, your nervrous and endocrine systems trigger the apocrine sweat glands and you may end up sweating before the workout itself. It is the exact same stimulantion your body gets during the sexual foreplay, stimulating your androgens and releasing sexual scents. Actually, this is your stress sweat. You will notice that you perspire more during increased emotional or psychological pressure. This may explain why you can smell the sweat when you are "turned on", or nervous before an important meeting.

If you are sweating excessively, then you might need to look at underlying causes such as low blood sugar, liver or kidney disease, diabetes, parasites, metabolic dysfunction, menopause, or prolonged extreme emotional stress.

How Much Do You Sweat?

The amount of sweat produced depends upon states of emotion, physical activity, and hormone levels. Interestingly, women have more sweat glands than men, but perspire less then the strong gender, even proportionally. This does not mean that women regulate body temperature better than males, however. The reason men usually sweat 40% more is that they are more active and they have greater energy expenditure. In fact, lower sweat rate provides less opportunity to dissipate body heat, thus raising body temperature. The average adult loses 540 calories with every liter of sweat and anywhere between 0.7 liters per day to 2.5 liters per hour.

Why Can You Smell the Sweat

Sweat itself does not have any smell. It is the bacteria and odors coming from other sources that are the real culprits. Perspiration with detectable odor is called bromohidrosis. Anaerobic bacteria, which flourish when your body doesn't have enough oxygen, may well be the cause of your body odor. As the body's metabolism goes to work, it gives off sweat which is the body's way of ridding itself of waste products. Any imbalances in metabolism will result in stronger odors.

strong>Toxins from our environment and waste products of metabolism might be responsible for the smell. When the organs of elimination such as liver, kidneys and intestines cannot dispose of them efficiently, wastes come out with sweat. Tobacco use is a major cause of body odor. Toxins of cigarette smoke mix with other elements of your body's chemistry and come out through the skin and lungs creating a distinct odor. If you stop smoking it may take several weeks for the body to rid itself of odor causing substances.

Depending on individual body chemistry, dietary imbalances may also cause body odor. Strenuous exercise can double mineral loss through increased sweating. Electrolytes like sodium, chloride, potassium, and magnesium are lost in the sweat which in turn disturbs mineral balance. Deficiency of magnesium or zinc, consuming large amounts of choline found in foods such as eggs, fish, liver and legumes, may result is a "fishy" smell. If you are one of these people, cut out these products and see if this is the cause of your odor. Certain foods and drinks, such as onions, garlic, curry, spicy foods, coffee and alcohol, fried and baked goods may contain rancid fats and oils that lead to body odor. Medications and large quantities of refined sugar may also be the cause of smelly sweat since sugar feeds bacteria and fungus on the skin.

Do you smell an acrid, ammonia-like sweat when you exercise? Ammonia has a sharp, penetrating pungent odor you can smell in cleaning products and bleech, cat urine, and sometimes sweat. The smell is common among professional athletes who train for hours on end. When you can recognize your slashing odor – it's time to stop training and supply your body with some energy and fluids. The reason behind is that your body started wasting your muscles.

Without getting enough calories to maintain all body's functions (coming from either protein, carbohydrates or fat), you will transform some lean mass into usable glucose. Since there is no metabolic pathway to convert fats into glucose, muscles serve as the preferable fuel. When you continue to exercise in the glycogen depleted state, muscle breakdown is accelerated. The noticable sweat smell comes from Nitrogen contained in the muscles, and ammonia is the byproduct of protein metabolism. So, if you really care about keeping your hard-earned valuable muscle tissue, try to replenish your energy and fluids before you start smelling your muscle waste. Ammonia can damage tissue and inhibit energy production – this is where hydration becomes extremely important. In the dehydrated state, all salts in the blood and lymph become more concentrated. So, proportion of ammonia to water increases, thus the smell is easier to detect. By drinking additional water you will dilute your body fluids and easily excete all metabolic wastes.

Regardless whether you can smell ammonia or not, sweating means water loss. Just 2 percent dehydration in the body will cause 20 percent drop in physical and mental performance! Can you imagine how damaging it can be for your workout?

Daily Tips

Shower or bath daily to remove bacteria from your skin, especially the armpits and groin area where the bacteria is most prevalent.

Deodorant soap is preferable as it helps fight bacteria more than regular soaps.

Loosely fitting clothes and natural fabrics allow the body to breathe better than synthetic tight clothes. Today you can buy clothes made with new wicking fabrics that pull moisture away from your skin, moving it to the surface of the fabric where it can evaporate.Wicking fabrics keep your skin dry, which is important for maintaining a cool body temperature in the summer and avoiding hypothermia in the winter. Examples of high-tech wicking fabrics are CoolMax polyester, Capilene or Polartec Power Stretch and MTS polyester.Wash your clothes frequently or the bacteria will grow and give the clothes unbearable smell.

Dietary Changes

Chlorophyll is a great deodorizer. One or two chlorophyll tablets or chlorophyll liquid taken with each meal may also help. Great sources of chlorophyll are parsley, alfalfa and other leafy greens will help neutralize body odor. Wheat grass may be taken daily on an empty stomach in the amount of 500 mg washed downed with a glass of water.

B vitamin (50 mg or higher), when combined with magnesium, will help reduce certain secretions that can be a cause of odor.

Sage leaves blended with tomato juice has been found to be very effective when taken as a dietary supplement daily.

Zinc and Magnesium will help balance your body's metabolism and reduce the cause of bad smell. Studies have shown that taking 30 to 50 mg of zinc and 200-500 mg of magnesium daily will dramatically reduce certain body odors, although you may need less. Zinc may also reduce perspiration and sweaty feet. However, it is wise to go above 15 mg only with a doctor's supervision as zinc may interfere with the absorption of copper, another essential trace mineral.

Find out more on the Australian Fitness:

Science of Sweat II - Immunity, Heat and Hormones
Science of Sweat III - How To Stop The Sweat
Testing Sweat