Is a Low-Carb Diet Safe For Kids?

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What exactly is a low carb diet, and are they safe for children? Could decreasing dietary carbohydrates help teenagers who are overweight?

Low Carb Diets - The History

Low-carb (low carbohydrate) diets are still very popular, with adults raving about the South Beach diet, the Atkins diet, and the plethora of packaged foods that are available as "low carb" alternatives.

When it comes to nutrition, however, we know that children aren't simply little adults.

Nutrient needs vary between adults and children, which raises the question: Are these diets safe for children to eat regularly? Can we translate what we know in adults into recommendations for children? And with the adolescent obesity epidemic of our era, could a low carb diet make a difference?

Low-Carb Diets

in order to discuss low carb diets, it's helpful to describe the nutrient proportions in a "regular" American diet. In a classic diet:

  • 10 to 12% of calories are from protein.
  • 50 to 60% of calories come from carbohydrates.
  • 30% of calories come from fat (and monounsaturated and polyunsaturated fats are preferred over saturated fats such as those found in animal products.)

In contrast, in a low carb diet:

  • Only 10 to 20% of calories come from carbohydrates.
  • The remaining 80 to 90% of calories come from proteins and fats.

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 carbohydrates.

We will talk about specific foods found in a low carb diet below, but first let's talk about the use of this diet in children.

Low-Carb Diets for Kids - Safety as a Bottom Line

It's important to first note that studies suggest a strict low carb diet may have a negative impact on short term and long term health of children and adolescents.

One survey of teen nutrition patterns found that those who ate more low-carb foods had a diet with fewer fruits and vegetables than those on a higher carb diet. These children also had a higher intake of meats and added fats resulting in higher cholesterol. In addition, those on lower carb diets consumed less fiber and vitamin C than those on a higher carb diet.

Long term effects were not evaluated in this study, but we know from many other studies that a diet high in fruits, vegetables, and fiber is important in warding off disease.

Another concern is that low-carb diets may be hard for kids to follow, and they may simply gain back any weight they lost on the diet when they return to their previous dietary practices. Some experts are also concerned that a high protein/low carb  diet could have long term negative effects on a child's heart and kidneys.

Low Carb Diet and Overweight Teens - Benefit and Controversies

We know that the incidence of childhood obesity is escalating in the United States.

The implications of this go far beyond "looks" and even the emotional ramifications of "looking fat." The health effects of childhood obesity, as in adults, range from from diabetes to sleep apnea.

Researchers have attempted to determine the reasons for the skyrocketing rate of childhood obesity. It may seem ironic that as weight among teens has increased, the number of calories consumed in a child's diet hasn't changed significantly over the past 30 years.

What researchers are guessing is that, while lack of exercise may play a big role, the amount and type of carbohydrates consumed is responsible. It's thought that high glycemic foods cause an excessive amount of insulin to be secreted after eating, which in turn leads to weight gain.

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. Researchers concluded that a low-carb "diet appears to be an effective method for short-term weight loss in overweight adolescents."

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.

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 or a registered dietician who has experience managing teens on low-carb diets.

Let's talk about exactly what foods are considered low carb, as well as what a modified low carb diet might look like.

Low-Carb Foods

Many foods that are high in carbs seem to be the things that kids like the best, for example, bread, pasta, corn, potatoes, cereal, and fruit juice.,

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

  • Lean meats, chicken and fish
  • Cheese
  • Eggs
  • Peanut butter
  • Greens, such as lettuce, spinach, and kale
  • 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)

Modified Low-Carb Diet or "Moderation in Everything"

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:

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.

Changing Your Child's Diet

Knowing something, and putting it in to action, are two separate things, as most parents understand all too well. Some kids are picky eaters, so what can you do to have the best chance for success?

  • Go it slow - Introduce changes in your child's diet slowly, rather than all at once.
  • Model healthy eating habits - The best thing you can do for your child's eating habits is to to eat well yourself.
  • Make it fun
  • Make it interesting - There are oodles of creative ideas online for making even a mundane meal more interesting.
  • Remember variety - A surprising finding in many studies has been that a variety of different foods can sometimes be as important as getting any particular nutrients.  Try to serve your child "the colors of the rainbow."
  • Again, remember moderation - Some changes, even when very healthy in moderation, can be unhealthy when taken to the extreme.
  • You may also wish to check out these weight loss tips for kids who just can't seem to lose weight.


Greene-Finestone, L., Campbell, M., Evers, S., and I. Gutmanis. Adolescents' low-carbohydrate-density diets are related to poorer dietary intakes. Journal of the American Dietetic Association. 2005. 105(11):1783-8.

Johnston, B., Kanters, S., Bandayrel, K. et al. Comparison of weight loss among named diet programs in overweight and obese adults: a meta-analysis. JAMA. 312(9):923-33.

Levine, M., Jones, J., and D. Lineback. Low-carbohydrate diets: Assessing the science and knowledge gaps, summary of an ILSI North America Workshop. Journal of the American Dietetic Association. 2006. 106(12):2086-94.

Schwingshackl, L., Hobl, L., and G. Hoffman. Effects of low glycaemic index/low glycaemic load vs. high glycaemic index/ high glycaemic load diets onoverweight/obesity and associated risk factors in children and adolescents: a systematic review and meta-analysis. Nutrition Journal. 2015. 14:87.

Slyper, A. The pediatric obesity epidemic: causes and controversies. Journal of Clinical Endocrinology and Metabolism. 2004. 89(6):2540-7.

Sondike, S., Copperman, N., and M. Jacobson. Effects of a low-carbohydrate diet on weight loss and cardiovascular risk factor in overweight adolescents. Journal of Pediatrics. 2003. 142(3):253-8.

Truby, H., Baxter, K., Barrett, P. et al. The Eat Smart Study: a randomised controlled trial of a reduced carbohydrate versus a low fat diet for weight loss in obese adolescents. BMC Public Health. 2010. 10:464.

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