Impact of Dehydration on Hair Loss and Hair Growth

Impact of Dehydration on Hair Loss and Hair Growth

Nearly two-thirds of the human body is water. Everyone knows they need to maintain this natural balance, yet many cut back on drinking the recommended amount of water daily. But did you know this could cause hair loss and affect hair growth?

Dehydration occurs when the body uses or loses more water than is replaced. It can leave calling cards on many parts of the body, starting with the hair, skin, and nails. If this sounds like you, the secret to restoring those luscious locks may be eight glasses of water away!

Dehydration and Hair Loss – how are they related?

Water is a source of energy for every cell in the body. It’s the same for hair follicles, which are the cells that generate new hair. When a person is dehydrated, they exhibit symptoms in their hair, including dryness, thinning, brittleness or increased breakage, dullness or loss of shine, loss of volume, itchiness in the scalp, and hair loss. Here are more clearly-defined ways in which good ol’ H2O influences the health and state of your hair:

  • It aids in delivering nutrients to the scalp and hair follicles

Dehydration cuts off the water supply and slows down blood flow to the hair follicles — this lops off essential vitamins that affect the hair’s integrity, volume, and thickness. When the water supply is low, the body will ration out the much-needed fluids to more vital parts of the body instead, such as the brain and heart. The roots will not be moisturised enough and can’t stimulate hair growth. And the hair follicle will be too dry, resulting in breakage and shedding.

  • It keeps hair moisturised and prevents drying and splitting

Severe dehydration can lead to the appearance of thinning hair, consistent with dry strands and split ends. Remember that hair needs moisture from the inside out — dehydration already decreases circulation to the scalp, and when this is compounded by exposure to the sun and elements, hair loss and balding accelerate.

  • It prevents infection by flushing out toxins and pollutants 

The moisture content of your scalp plays a crucial role in its function as a protective barrier. When dehydrated, the scalp becomes drier; as the scalp becomes drier, it can start to flake off; and when it flakes off, it can become itchy and painful. Since the scalp is highly dehydrated, it may “break” and increase the risk of developing skin infections when you touch or scratch it. Drinking water flushes toxins and impurities in the body out, restoring nutrients to the scalp.

Advice on staying hydrated

You may have heard of the general rule of thumb: the 8×8 rule, meaning eight glasses of water daily with eight ounces each. Some round this up to about 3 to 4 litres each day. Depending on body weight, activity level, and climate, you may need more.

Remember to top up throughout the day by carrying a water bottle whenever you’re out. You can also download a hydration app that sends notifications at intervals to remind you to drink water. And while you’re at it, why not also mark up your water bottle with ounces or hours to show how much H2O you’ve guzzled throughout the day.


Hair loss from dehydration is one of the easiest causes of hair loss to reverse. However, drinking water is not a magic elixir to solve your hair problems. Your problems may be more likely due to genetics, stress, medical conditions, medications, or scalp disorders unless chronically hydrated. Water can work wonders, but hair replacement systems are the way to go when hydration fails to solve your problems!

At Rehair Lab, we specialise in hair replacement in Singapore to help you get that refreshed (and hydrated) new look. Consider consulting with our hair replacement specialists today for effective solutions and support services to address your hair loss concerns.