Updated December 15, 2014.

Low-carb diets, such as the Atkins diet and South Beach diet, are fairly popular among people.

Do they work for kids?

Are they safe?

Low-Carb Diets

In a typical low-carb diet, instead of a classic diet that is made up of:

• 10 to 12% of calories from protein
• 50 to 60% of calories from carbohydrates
• 30% of calories from fat, with a preference for monounsaturated and polyunsaturated fats

you will learn to count carbs and get to a goal where you eat just enough carbs, so that you lose weight, but don't have a lot of cravings that make you hungry.

This means that you will get way fewer than 50 to 60% of your calories from carbohydrates — maybe just 10 to 20%, with the rest coming from protein and fat.

Most low-carb diets also advocate avoiding sugars or simple carbs that have a high glycemic index, which can raise blood sugar faster than high-fiber complex carbs.

Low-Carb Foods

Many foods that are high in carbs seem to be the things that kids like, i.e., bread, pasta, corn, potatoes, cereal, raisins, milk and fruit juice.

On the other hand, low-carb foods, in addition to prepackaged low-carb meals and snacks, include:

• lean meat, chicken and fish
• cheese
• eggs
• peanut butter
• greens (lettuce, spinach)
• broccoli
• green beans
• tomatoes
• carrots
• strawberries
• watermelon
• apples
• blueberries
• peaches
• cantaloupes
• unsweetened applesauce
• nuts
• sunflower seeds
• sugar-free jello
• sugar-free yogurt
• unsweetened soy milk
• low-carb milk (Hood Calorie Countdown Dairy Beverage, which has artificial sweeteners)
• low-carb bread
• low-carb pasta (Dreamfields pasta)

Low-Carb Diets for Kids

Although very few research studies have been done on low-carb diets for kids, one study did show that overweight teens did better on a low-carb diet vs.

a low-fat diet. In this study, Effects of a low-carbohydrate diet on weight loss and cardiovascular risk factor in overweight adolescents, researchers concluded that a low-carb "diet appears to be an effective method for short-term weight loss in overweight adolescents."

Although they admitted that this was "a preliminary study with a few limitations" and that "further long-term follow-up studies must be conducted to confirm these findings," it does offer some guidance for parents of teens who really want to try a low-carb diet.

Teens in this study ate no more than 20g of carbs each day for two weeks, which was then increased to 40g of carbs during weeks 3 through 12 by allowing them to eat more fruits, nuts and whole grains. They were allowed to eat as much protein, fat and overall calories as they wanted. In comparison, a group of teens in a low-fat diet was limited to less than 40g of fat a day, 5 servings of starch and as many fat-free dairy foods, fruits and vegetables that they wanted for 12 weeks.

Interestingly, after one year, of 36 children in the study, only one teen on the low-fat diet, but 8 on the low-carb diet, came back for follow-up. The researchers concluded that may mean that the low-carb diet might have been easier for the teens to follow.

Low-Carb Diet Controversies

More studies should be done proving that these diets are effective before a lot of overweight teens start going on low-carb diets, but the other big question is whether or not they are safe for children and teenagers.

One survey of teen nutrition patterns found that those who ate more low-carb foods often had a diet that consisted of few fruits and vegetables and was low in fiber and vitamin C, but was high in cholesterol and fat. And more of these teens were at risk of being overweight or were overweight as compared to the teens who ate more non low–carb foods.

The other concerns are that low-carb diets may be hard for kids to follow, and they may simply gain any weight back that they did lose once they stopped the diet. Some experts are also concerned about the long term health effects that a high-protein/low-carb diet could have on a child's heart and kidneys.

When you consider that some overweight teens have "tried everything" and continue to gain weight and some even have weight loss surgery, you have to wonder if trying a low-carb diet has to be safer than the alternatives. Due to the risks and complex nutritional needs of children, a low-carb diet should likely only be tried under the guidance and supervision of your pediatrician registered dietician who has experience managing teens on low-carb diets.

Modified Low-Carb Diet

Since many experts blame the rise in childhood obesity on the fact that kids eat more carbs these days, especially more simple sugars, even if your child doesn't start a low-carb diet, taking a closer look at carbs is a good idea.

In addition to more exercise and eating more high-fiber foods, avoiding high-calorie foods, high-fat foods and foods with any trans fats or more than 10% saturated fat may help to encourage the eating of more low-carb foods and avoid high-carb foods made up of simple sugars, such as:

• white bread (choose whole grain bread instead)
• soda and fruit drinks
• sugary breakfast cereals
• potato chips
• cakes, pies and brownies
• candy and other junk food

Together with low-fat milk and age-appropriate portion sizes, this modified low-carb diet could be a good diet for kids, because it isn't overly restrictive and is easy to follow.

<sub>Sources:

Low-carbohydrate diets: Assessing the science and knowledge gaps, summary of an ILSI North America Workshop. Levine MJ - J Am Diet Assoc - 01-DEC-2006; 106(12): 2086-94.

Sondike S.B., Copperman N., Jacobson M.S.: Effects of a low-carbohydrate diet on weight loss and cardiovascular risk factor in overweight adolescents. J Pediatr 142. 253-258. 2003.

Adolescents' low-carbohydrate-density diets are related to poorer dietary intakes. Greene-Finestone LS - J Am Diet Assoc - 01-NOV-2005; 105(11): 1783-8.

The pediatric obesity epidemic: causes and controversies. Slyper AH - J Clin Endocrinol Metab - 01-JUN-2004; 89(6): 2540-7.</sub>