Home » Nutrition Channel » Three Dehydration Signs: Weight Loss, Dark Urine, Thirst

Three Dehydration Signs: Weight Loss, Dark Urine, Thirst

A youth athlete's hydration status before, during and after a sport practice or game, and how their hydration status changes, are particularly important. As a parent, how can you tell if your child is dehydrated? There are several ways to check if a child or teenager is dehydrated before and after sports, or whether their hydration status has changed:

  • Urine Color: Researchers have found that children as young as 7 can be taught to use urine color to determine if they are dehydrated if descriptive words or phrases are used that they are already know:
    • Light yellow or relatively clear urine ("lemonade") means the athlete is hydrated.
    • Bright yellow urine ("mellow yellow") means that the athlete is slightly to moderately dehydrated
    • Brownish urine ("apple juice") means the child or teenage athlete is severely dehydrated.

The best way to evaluate urine color is for the child to urinate into a clear cup of some kind. However, it can still be determined inside the toilet bowl as long as the dilutive effect of the extra water is taken into account.

A helpful way for kids to remember the link between urine color and hydration is for their goal to remind them to "stay in the clear" because a clear or light yellow urine color means they are staying hydrated.

Am I Hydrated Urine Color Chart 

  • Percentage of weight loss: Weight lost during a practice or game is water the body needs to replace in order to function properly. Determining the weight lost can also aid in replacing fluids after exercise. For every pound of water lost, ½ liter of fluids needs to be consumed. In order to determine percent dehydration simply weigh the youth athlete immediately before practice and immediately after.
    • Ideally, a child should only be wearing shorts while on the scale. Shoes, socks, and other articles of clothing that can soak up sweat should be removed.
    • To find out the the percentage of dehydration subtract the post-weight weight from the pre-test weight, divide that number by the post-test weight and multiply that number by 100. For example, a 110 pound child who loses 2 pounds during sports is 1.8% dehydrated (110-108/110 x 100= 1.8%).
    • 1-2% dehydration can adversely affect performance; percentage losses greater than 3% can have adverse health effects.
  • Thirst: Studies of children and teenagers have shown that thirst is not a reliable indicator of hydration status. Although the precise reason is unclear, experts speculate that it is likely due to the fact that children and teens playing sports get distracted by the enjoyment of the sport. While a lack of thirst does not necessarily indicate the individual is hydrated, the fact that a child or teenager is thirsty, does indicate that the individual is dehydrated to one degree or another. This means that asking a child if she is thirsty while playing sports is not a good way to measure hydration status, but if the child voluntarily expresses thirst, it can be safely assumed the child is already dehydrated.

A good way to remember these hydration measures is to use a mnemonic": WUT, which means if there is Weight loss, a darker Urine color, and Thirst is present, the child is dehydrated and re-hydration strategies should be followed.

Urine Specific Gravity

Teenagers who participate in organized sports programs that conduct hydration checks may have their urine checked for specific gravity. A small telescope-looking instrument determines the density of the urine as compared to the density of water. The higher the density, or specific gravity, the more dehydrated the sample is. A urine specific gravity of 1.000-1.019 is considered a hydrated youth, 1.020-1.027 is considered a minimal to moderate dehydrated youth, and 1.028-1.035 is considered severely dehydrated

Progressive effect

If a youth is experiencing either (a) an increase in the number of dehydration symptoms they are experiencing, or (b) an increase in the severity of the symptoms, than dehydration is present and may be getting worse.

The progressive effects of dehydration are serious. As a child becomes dehydrated, heart rate increases, blood flow to the skin decreases, and a body temperature can rise steadily to dangerous levels. To avoid a potentially life-threatening medical emergency, parents and coaches need to be familiar with the symptoms of and treatment for heat-related illnesses

Updated October 29, 2015


NOW Available in KINDLE