Dehydration occurs when your body does not have as much water and fluids as it should. Dehydration can be caused by losing too much fluid, not drinking enough water or fluids, or both. Vomiting and diarrhea are common causes.

Infants and children are more susceptible to dehydration than adults because of their smaller body weights and higher turnover of water and electrolytes. The elderly and those with illnesses are also at higher risk.

Dehydration is classified as mild, moderate, or severe based on how much of the body's fluid is lost or not replenished. When severe, dehydration is a life-threatening emergency.

Symptoms

• Dry or sticky mouth
• Low or no urine output; concentrated urine appears dark yellow
• Not producing tears
• Sunken eyes
• Markedly sunken fontanelles (the soft spot on the top of the head) in an infant
• Lethargic or comatose (with severe dehydration)

In addition to the symptoms of actual dehydration, you may also have vomiting, diarrhea, or the feeling that you "can't keep anything down," all of which could be causing the dehydration.

Treatment

Drinking fluids is usually sufficient for mild dehydration. It is better to have frequent, small amounts of fluid (using a teaspoon or syringe for an infant or child) rather than trying to force large amounts of fluid at one time. Drinking too much fluid at once can bring on more vomiting.

Electrolyte solutions or freezer pops are especially effective. These are available at pharmacies. Sport drinks contain a lot of sugar and can cause or worsen diarrhea. In infants and children, avoid using water as the primary replacement fluid.

When to Contact a Medical Professional

Call 911 if you or your child have the following symptoms

• Dizziness
• Lightheadedness
• Lethargy
• Confusion

Call your doctor right away if you or your child has any of the following symptoms:

• Not producing tears
• Sunken eyes
• Little or no urine output for 8 hours
• Dry skin that sags back into position slowly when pinched up into a fold
• Dry mouth or dry eyes
• Sunken soft-spot on the top of your infant's head
• Fast-beating heart
• Blood in the stool or vomit
• Diarrhea or vomiting (in infants less than 2 months old)
• Listlessness and inactiveness

Also call your doctor if you are not sure whether your attempts to give your child proper fluids are working.

Even when healthy, drink plenty of fluid every day. Drink more when the weather is hot or you are exercising.

Carefully monitor someone who is ill, especially an infant, child, or older adult. If you believe that dehydration is developing, consult a doctor before the person becomes moderately or severely dehydrated. Begin fluid replacement as soon as vomiting and diarrhea start -- DO NOT wait for signs of dehydration.

Dehydration when playing sports is common. Water is the best choice to ensure hydration, Any activity that lasts less than 60 minutes doesn't require electrolytes, so you can safely skip electrolyte-enriched sports drinks such as Gatorade .

To avoid dehydration:

-- Before exercise, drink 4 to 8 ounces
-- During activity, drink 4 ounces every 15 minutes
-- After exercise, drink 16 to 24 ounces per every pound lost

NIH
Committee on Sports Medicine and Fitness. American Academy of Pediatrics.

Reuters Health is reporting about a study linking obesity and school lunches. Philadelphia schools that cut out soda, revamped snack selections and took other measures to prevent childhood obesity were able to halve the odds of students becoming overweight by sixth grade, a study has found.


Among fourth-graders at five schools that instituted the new nutrition policy, 7.5 percent became overweight over the next 2 years, compared with 15 percent of students at five city schools that did not make the changes, researchers report in the journal Pediatrics.

The findings show that a comprehensive approach to battling childhood obesity in schools can make a significant difference, according to lead researcher Dr. Gary D. Foster of Temple University.

Schools have been at the center of the controversy over what to do about U.S. children's rising rates of overweight and obesity. Critics have pointed to vending machines, sugary "a la carte" items in school cafeterias, and reductions in gym class as part of the problem.

At the same time, schools are considered the ideal place for children to learn healthy eating and exercise habits, and various school-based programs have been developed with that aim. The results have been mixed, however.

For their study, Foster and his colleagues evaluated a program developed by a non-profit community group called the Food Trust. Ten schools enrolled in the study; half were randomly assigned to adopt the nutrition program, while the other half served as a comparison group.

Schools in the program made an array of changes. They replaced soda with water, low-fat milk and 100-percent fruit juice, and rid vending machines and cafeterias of snacks that did not meet certain nutrition criteria. They educated students on how diet and exercise affect their health, and gave them raffle tickets for bikes and other prizes to reward them for choosing healthy snacks.

The schools also got parents involved through meetings and nutrition workshops that encouraged them to give their kids more fruits, vegetables and other healthy foods.

Among the 1,349 students Foster's team followed from fourth to sixth grade. As mentioned, there was about a 50 percent reduction in the incidence (new cases) of overweight at the end of 2 years among the children attending the program schools, while no changes were seen among the children attending the schools without a program.

The prevalence (total number) of overweight children also declined during the study period in the program group. However, no differences in the prevalence of obesity were seen between the program group and the comparison group.

The results, Foster told Reuters Health, underscore the benefits of schools having a comprehensive nutrition program, rather than taking only individual measures -- like removing vending machines, for instance.

He and his colleagues also stress that the urban schools in this study had largely low-income, minority student populations -- children who are at particularly high risk of obesity. Black children appeared to particularly benefit from the nutrition policy.

In the sixth grade, the study found, African-American children in these schools were 41 percent less likely to be overweight than African Americans in the comparison schools.

Despite the success, Foster's team writes, the fact that 7.5 percent of children in the program schools still became overweight shows that even more needs to be done.

They say that obesity-prevention programs should start before fourth grade, and possibly include a broader range of measures -- such as devoting more time to gym class and enlisting the corner stores near schools to offer healthier snack options.

SOURCE: Pediatrics, April 2008.