Dehydration & Extreme Heat

Dehydration and heat

In order to stay healthy, our body temperature needs to stay at approximately 37⁰C. Usually, the body cools itself by sweating, which accounts for up to 80 percent of the body’s heat loss. When you don’t drink enough fluids during hot weather, you may become dehydrated. This causes a decrease in sweat production and your body temperature will keep rising as your body struggles to cool down. This can lead to heat‐related illnesses including:

  • heat rash
  • cramps
  • dizziness
  • fainting
  • heat exhaustion
  • heat stroke
  • potential worsening of any existing medical conditions.

Heat stroke is the most serious heat‐related illness and occurs during times of extreme exposure to the sun. In cases of heat stroke, a person does not sweat enough to reduce their body temperature normally. The condition can develop quickly and is a medical emergency requiring immediate treatment.

How common is dehydration due to extreme heat?

Dehydration is a very common heat‐related illness that can be life threatening if left untreated. Although anyone can become dehydrated and go on to develop heat‐related illnesses, certain people are more at risk than others. The groups that are most susceptible to dehydration include:

  • People working or exercising outside in extreme heat and/or humidity: when the air is humid, sweat can’t evaporate and cool you as quickly as it normally does. This can lead to an increase in body temperature and an increased need for fluids.
  • People with chronic illnesses.
  • Infants and children: This is due to their small body weights and high turnover of water and electrolytes.
  • Elderly people: As we age our bodies are less able to conserve water, thirst becomes less acute and we are less able to respond to changes in temperature.

It is predicted that the number of cases of heat‐related illness will become more prevalent under the influence of global warming. Fortunately, dehydration and heat‐related illness is usually preventable. Your response to a heat wave is a key factor in managing the development of heat related illnesses.

How can I prevent dehydration during these periods?

During very warm temperatures , make sure to drink a lot of cool fluids, before you feel thirsty, to decrease your risk of dehydration. If you are eating less, you may need to drink more fluids. Also try to include more fruit and vegetables in your diet, as they contain a high amount of water. Stay cool by dressing for the hot weather: wear loose fitting, light coloured clothing made from breathable fabric. Keeping your home cool is another way to prevent dehydration and heat‐related illnesses during a heat wave. Block out the sun by keeping curtains and blinds closed during the day and prepare food which doesn’t need to be cooked in the oven. At night, open your windows to let cool air into the house. Try to avoid sun exposure and plan outdoor activities for the coolest part of the day whenever possible.

Do I need to see my Doctor if I’m dehydrated?

In cases of mild dehydration, simple rehydration can be achieved by drinking fluids. Products that restore fluid levels, salt balance and electrolytes are ideal.Gastrolyte Electrolyte Hydration products provide a convenient way to help replace the lost fluids and electrolytes as a result of mild dehydration due to extremely hot weather. It is available as:

  • Gastrolyte Ready to Drink formula
  • Gastrolyte sachets or
  • Gastrolyte effervescent tablets that are dissolved in water

In cases of severe dehydration, medical treatment from your doctor or health care professional should be sought immediately. Severe dehydration may cause signs and symptoms such as:

  • extreme thirst
  • a very dry mouth and skin
  • lack of sweating
  • little or no urination
  • shrivelled skin
  • sunken eyes
  • low blood pressure
  • rapid breathing and heart rate
  • fever
  • adults may also be irritable and confused
  • children may exhibit extreme fussiness and/or sleepiness.

Always read the label. Follow the directions for use. If symptoms persist, talk to your health professional. Vitamin supplements should not replace a balanced diet

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