IN 2009, the centers for disease control reported that fewer than 10 percent of U.S. high school students are eating the combined recommended daily amounts of fruits and vegetables. Also in 2009, a study was released that found that supplementation with multivitamins during the first years of life may reduce the risk of allergic disease at school age. Two years earlier, an international study lasting 12 months reported that even in well-nourished school-aged children, fortification with multiple micronutrients can result in improvements in verbal learning and memory.
At least on its face, there is a good case to be made for vitamin and mineral supplementation for children and adolescents. Research increasingly is showing that the diet and everyday environmental factors during the first three to five years of life can have important consequences in the areas of mental health, educational performance and the ability to interact socially. Similarly, early nutrition helps to determine whether the child will grow up obese, develop diabetes or suffer from heart disease in later life. In adolescents, nutritional support improves concentration and other aspects of performance and behavior.
Infant nutrition is a harder case and not as clear-cut. It long has been known that an infant’s diet is important for mental development. On the one hand, the mother’s eating habits, especially consumption of omega-3 fatty acids, and overall health during pregnancy may contribute greatly to her child’s health and even determine her child’s risks for major diseases in adulthood. On the other hand, it is difficult to intervene nutritionally at just the right level during the first six months of life. In part this is because it is easy with infants to go beyond the accepted tolerable upper limit of intake for certain nutrients, especially vitamins A and folic acid and the mineral zinc. The one fortification that most researchers would agree is justified is an increased intake of the omega-3 fatty acids.
Starting children off on the right foot
It is clear that Americans have been losing the earliest of nutritional battles. For instance, obesity has reached epidemic proportions in children. Estimates are that 25 percent of children in the U.S. are overweight and an additional 11 percent are obese. This is cause for concern given that children who are obese at age 4 have a 20 percent risk of being obese in adulthood. If they continue to be overweight as adolescents, they have an 80 percent chance of being overweight or obese as adults.
With obesity comes diabetes. According to Dr. Lori Laffel, head of the pediatric unit at Boston’s Joslin Diabetes Center. “Over the years, we always saw an occasional child with type 2 [diabetes]. It was a handful a year.” That was before the 1990s, when overweight parents began to bring in their similarly large children with type 2 diabetes. In that decade, the number of children with so-called “adult” diabetes increased approximately 500 percent, and the rate has doubled again since then. Similar increases are reported at other institutions. Regarding this type of diabetes in children, Dr. Phillip Lee, head of pediatric endocrinology at UCLA, says, “we just didn’t see it. Now referrals of type 2 are almost 50 percent of our diabetes cases.” Diabetes and pre-diabetes (also called Syndrome X or the metabolic syndrome) ominously are linked to not just obesity, but hypertension, cardiovascular disease and yet other conditions.
Before considering supplements as a solution to childhood nutritional problems, two issues need to be tackled. First, there is the problem of diet. Especially sugar in the diet. Keep in mind that sweetened drinks, not just sodas, but the sugared 10 percent juice drinks, have almost totally displaced water in the lives of modern American children.
Food nutritionists at Cornell University during a two-month study found that children do not reduce how much food they eat at meals to match the number of calories they consume in sweetened drinks. Instead, the more sweetened drinks they consume, the greater their daily caloric intake and the greater their weight gain. According to David Levitsky, this survey of 30 children aged 6–12 supports previous findings that excessive sweetened drink consumption adversely affects nutrition and promotes obesity in school-age children. For the purposes of this study, sweetened drinks included fizzy drinks, fruit punch, and bottled tea or drinks made from fruit-flavored powders, such as grape and lemonade. According to the study, children who drank more than 16 ounces a day of sweetened drinks consumed four ounces less milk than children who avoided sweetened drinks. Their diets supplied 20 percent less phosphorus, 19 per cent less protein and magnesium, 16 percent less calcium and 10 percent less vitamin a plus less zinc even though these children also took in 244 more calories a day from these beverages. The ingestion of sweetened drinks led to the consumption of only 2 ounces less solid food, although such drinks routinely displaced milk.
Second, and on the other side of the energy equation, children now exercise less than in previous generations. According to a study by the Centers for Disease Control, 22.6 percent of American children (aged 9–13) do not engage in any free-time activity. Nearly two-thirds of these children do not participate in any organized physical activity during their non-school hours.
Nutrient recommendations for children
Multivitamin—mineral supplementation for children does not need to involve heroic amounts of nutrients. In fact, trials exhibiting success in already supposedly well-nourished children often have involved daily vitamin-mineral supplementation at only roughly 50 percent of the U.S. Recommended Daily Allowance (RDA) for 3 to 14 months versus placebo. Depending on the study, benefits have been demonstrated in the areas of attention- concentration, verbal learning and memory, non-verbal intelligence and overall behavior. The impact is especially noticeable in children with antisocial and delinquency traits, but benefits routinely have been found, as well as, in children and teens supposedly beyond any need for nutritional intervention. A major recent review of 20 randomized placebo-controlled trials concluded, “multiple micronutrient supplementation may be associated with a marginal increase in fluid intelligence and academic performance in healthy school children but not with crystallized intelligence.”
Dietary Reference Intake (DRI) tables have been developed by the Institute of Medicine’s Food and Nutrition Board and are available from various sites on the Internet. Here is one of these resources:
Inasmuch as the tables are copyrighted, they cannot be reproduced here. The main points to keep in mind are these: first, supplementation does not need to be at high levels to deliver benefits. Many or even most successful trials supplemented only on the order of 50 percent of suggested daily intakes. Second, the suggested intakes of nutrients vary with age, body size, sex and activity. Let’s take vitamin B1 (thiamin) as an example of how age and sex can influence requirements. Children 1–3 years old require 0.5 Mg/day, 4–8 years require 0.6 Mg/day, boys 9–13 years require 0.9 and boys 14–18 require 1.2 Mg/day, this last being also the typically required adult male intake level. Girls aged 9–13 years also have a recommendation of 0.9 Mg/day, but only 1.0 Mg/day at ages 14–18 years and then 1.1 Mg/day at age 19 and older. Parents need not slavishly adhere to nutrient tables. The point is to find a general and broad spectrum multivitamin and mineral supplement that supplies roughly 50–100 percent of nutrients for the age of the child. Just “being in the ballpark” usually is good enough.
Nutrient recommendations for teenagers
From the perspective of an adult, most teenagers are eating machines. As with children, at the present time teenagers are likely to consume predominantly “empty” calories. Most American teens do not take vitamins and even among those who do take supplements, several micronutrients usually are consumed at inadequate levels. In one study, more than one-third of adolescents had dietary intakes of vitamins A and E, calcium, and zinc that were less than 75 percent of the U.S. Recommended Dietary Allowance. Recommendations here are as with children: find a general and broad spectrum multivitamin and mineral supplement that supplies roughly 50–100 percent of recommended nutrients for the age, gender and activity level of the adolescent in question.
Attention Deficit Disorder (ADD)/Attention Deficit Hyperactivity Disorder (ADHD)
Besides the recent disturbing trends towards obesity and diabetes in children and adolescents, the most significant concern in American children may be the incidence of ADD/ ADHD. According to the National Institute of Mental Health (NIMH), ADHD affects approximately 2 million American children or approximately 3 to 5 percent of the school-age population and is about four times more common in boys than in girls. ADHA usually becomes apparent at about age 3. Symptoms include inattention, inability to concentrate, failure to listen when spoken to, hyperactivity, squirming, talking out of turn, impulsiveness, disruptive behavior, sleep problems, and poor learning ability.
A number of nutritional scientists argue that ADHD is a birth defect caused by deficiencies of maternal DHA (docosahexaenoic acid) during pregnancy and while nursing, and the virtual absence of DHA and AA (arachidonic acid) in infant formulas. DHA in particular is required to support fetal visual acuity, neurological and brain development in the womb and in early life. As a point of information, AA is a long-chain omega-6 fatty acid found primarily in meat and eggs, whereas the omega-3 fatty acids EPA (eicosapentaeonoic acid) and DHA are found primarily in the fat of cold-water fish. A related omega-3 fatty acid, alpha-linolenic acid (ALA), is found in flax and pumpkin seeds, walnuts, and in eggs from hens raised on grass or special diets instead of grains. Even meat and butter from animals raised on grass (rare in the U.S. today) may provide substantial amounts of ALA.
ADD/ADHD is highly controversial. At a consensus development panel conducted by the National Institutes of Health on ADHD in November 1998, it was reported, “we do not have an independent, valid test for ADHD, and there are no data to indicate that ADHD is due to a brain malfunction. Further research to establish the validity of the disorder continues to be a problem. This is not unique to ADHD, but applies as well to most psychiatric disorders...” Some doctors report various brain metabolic imbalances, but these, too, are controversial.
There was a 2.5-fold increase in the prevalence of methylphenidate (Ritalin) treatment of youths with ADD between 1990 and 1995 in the United States. In all, approximately 2.8 percent (or 1.5 million) of U.S. youths aged 5 to 18 were receiving this medication in mid-1995. Data for treatment rates in the U.S. is inconsistent. One Journal of the American Medical Association (JAMA) article published in 1998 estimated that 3–6 percent of the school-aged population is being treated with psychotropic drugs, mostly stimulants. Noteworthy is the fact that a U.K. review from 2004 found that in that country in 1999 the rate of treatment for ADD in boys was 5.3 Per 1,000 boys—that is, one tenth the rate of the U.S.! This suggests that there is either some terrible environmental flaw present in the U.S. or some terrible error in diagnosis of ADD/ADHD in this country.
There also is the issue of treatment. In animals, exposure to Ritalin (methylphenidate) during developmental stages damages the personality. According to William Carlezon of McLean Hospital and Harvard Medical School in Boston, a primary researcher in this area, “rats exposed to Ritalin as juveniles showed large increases in learned-helplessness behavior during adulthood, suggesting a tendency toward depression.”
Obviously, the implications of the above are serious, and even more so when it is realized that ADD/ADHD stimulant drugs, such as Ritalin, work only for the first few months of treatment.
At most, the good effects may last 14 months. Moreover, the FDA in 2009 actually had to urge caution in interpreting a study linking stimulants to increased risk for sudden death in children.
Food additives and colors long have been suspected of inducing ADHD in susceptible individuals. Diets that eliminate such food adulterants sometimes have proved to be wildly successful, reducing symptoms in the range of 78 percent in comparison with controls. This was a diet of containing only rice, meat, vegetables, pears and water for five weeks. When restricted foods were added back to the diet, there was a relapse rate of 63 percent. Especially pernicious may be food colors and sodium benzoate.
Finally, there are some safe and practical suggestions for supplementation that may help. Chief among these is supplementation with omega-3 fatty acids. German scientists found a beneficial effect with a combination of omega-3 and omega-6 fatty acids as well as magnesium and zinc consumption on attentional, behavioral, and emotional problems of children and adolescents. Some trials indicate that even zinc supplementation by itself may be beneficial if a particular protocol is followed.
The supplement alpha-lipoic acid has been used successfully in a study at UCLA to improve the symptoms of adult ADHD sufferers. Inasmuch as lipoic acid improves blood sugar regulation and the utilization of glucose by the brain, this suggests a prediabetes link to ADHD. Barry Sears has written that contradictory results with regard to omega-3 supplementation may be expected because some studies tend not to control dietary intake of high-glycemic carbohydrates (sugar and starch), and do not provide their study groups with sufficiently high doses of DHA and/or EPA. For whatever reason, almost no attention has been paid to the insulin resistance aspect of ADHD, yet ADHD is highly prevalent among obese patients and highest in those with extreme obesity. A recent European review found that empirically based evidence suggests that obese patients referred to obesity clinics may present with higher than expected prevalence of ADHD and all reviewed studies indicate that subjects with ADHD are heavier than expected. One common causal mechanism linking ADHD and excessive weight is a disruption in the “reward” receptors of the brain based on the chemical dopamine. Recent work shows that the excessive consumption of sugars actually alters brain receptors such that individuals in the future feel the need— based on lasting changes in brain physiology and chemistry— to eat sugar and other refined carbohydrates.
Children and adolescents often can benefit from nutritional supplementation. For most, a simple multivitamin and mineral supplement providing 50 to 100 percent of the currently suggested daily intake of vitamins and minerals may be enough. For others, especially those who are performing below par in terms of attention, memory, verbal functioning and emotional balance, additional omega-3 and omega-6 fatty acids as well as magnesium and zinc, perhaps alpha-lipoic acid, may be in order. Reducing the consumption of sugars and other refined carbohydrates and increasing physical activity almost always is a good practice, as well.
Dallas Clouatre, PhD
Dallas Clouatre, Ph.D. earned his A.B. from Stanford and his Ph.D. from the University of California at Berkeley. A Fellow of the American College of Nutrition, he is a prominent industry consultant in the US, Europe, and Asia, and is a sought-after speaker and spokesperson. He is the author of numerous books. Recent publications include "Tocotrienols in Vitamin E: Hype or Science?" and "Vitamin E – Natural vs. Synthetic" in Tocotrienols: Vitamin E Beyond Tocopherols (2008), "Grape Seed Extract" in the Encyclopedia Of Dietary Supplements (2005), "Kava Kava: Examining New Reports of Toxicity" in Toxicology Letters (2004) and Anti-Fat Nutrients (4th edition).