Think back to your childhood for a minute. Do you remember your classmate—likely more than one—who was taunted in the school cafeteria, who sat by himself on the bleachers during recess, and who the other children called names like “fatty” and “pig face?” If it sounds harsh, it is.
Childhood obesity has psychological implications that start early on but leave scars well into adulthood, if not for an entire lifetime.
And then there’s the toll that childhood obesity takes on physical health. Statistics show this is a problem on the rise, globally and here in the U.S.
Childhood Obesity is a Growing Health Crisis
The World Health Organization (WHO) calls childhood obesity one of the most serious public health challenges of the 21st century and advises its prevalence has increased at an alarming rate. For example, says WHO, in 2016, the number of overweight children under the age of five is estimated to be more than 41 million globally.
The latest data (2015-2016) from the Centers for Disease Control and Prevention (CDC) show a prevalence of obesity in those ages 2-19 at 18.5%, up from 14% in 1999-2000.
In this week’s blog, we’ll focus on this important topic: obesity in children. And because our focus here at OmegaQuant is to educate about the role of omega-3s EPA and DHA in a healthy diet, we’ll specifically examine two new studies about omega-3 and obesity in children.
Childhood Obesity Definition
Simply put, childhood obesity is a condition in which a child is significantly overweight for his or her age and height.
More specifically, the CDC defines childhood obesity as a body mass index (BMI) at or above the 95th percentile for children and teens of the same age and sex. The CDC identifies childhood obesity as a complex health issue with serious consequences—one that affects nearly 14 million children and adolescents in the U.S.
The reasons for weight gain in children and teens are similar to those in adults. They include genetic and behavior factors and can also be influenced by education, income and a person’s community—all of which can affect the ability to make healthy choices.
Childhood obesity can result in both short- and long-term consequences. From a psychological standpoint, childhood obesity is related to social problems such as bullying, and can create low self-esteem, anxiety and depression. Physical problems include asthma, sleep apnea, joint and muscular-skeletal discomfort.
Sadly, children with obesity are more likely to become adults with obesity—a condition associated with increased risk for cancer, heart disease and type 2 diabetes.
So what, if anything, can be done about obesity in children?
The answers are not surprising—as they mirror the health advice given to adults with weight problems. Finding the right support system, including a social worker or therapist or a registered dietitian with a specialty in the field can be helpful for those who can afford them or have access to community or government assistance.
And as with adults, physical activity is key. Children ages 3 through 5 should be physically active throughout the day and those between ages 6-17 should engage in at least 60 minutes of moderate to vigorous physical activity daily, according to government recommendations.
The recommendation to follow a healthy eating pattern throughout life is one of the key takeaways from the government’s Dietary Guidelines for Americans. For adults, that includes a recommendation of at least 8 ounces of seafood per week (2–3 servings, based on a 2,000 calorie diet). Pregnant or breastfeeding women should eat between 8 and 12 ounces of a variety of seafood per week, from choices that are lower in mercury.
So what about children? The FDA advises to serve fish to children 2 and older 1–2 times per week, but in smaller portion sizes than for adults. On average, a serving size is about 1 ounce for children ages 2-3 years, 2 ounces for children ages 4-7 years, 3 ounces for children ages 8-10 years and 4 ounces for children over age 11.
Omega-3 EPA and DHA are found in abundance in fish and other seafood, but especially in salmon, sardines and tuna.
According to a recent article posted by the Academy of Nutrition and Dietetics, the current Recommended Adequate Intakes of omega-3 for kids range from 0.5 grams/day (for ages 0-12 months) up to 1.1 grams/day and 1.6 grams/day for girls and boys, respectively (ages 14-18). (See chart below for more specific recommendations per age group.)
The current Recommended Adequate Intakes of Omega-3s for kids are:
- 0 to 12 months: 500 mg/day
- 1 to 3 years: 700 mg/day
- 4 to 8 years: 900 mg/day
- 9 to 13 years (boys): 1.2 grams/day
- 9 to 13 years (girls): 1.0 grams/day
- 14 to 18 years (boys): 1.6 grams/day
- 14 to 18 years (girls): 1.1 grams/day
(Source: Do Kids Need Omega-3 Fats? —American Academy of Nutrition & Dietetics, August 12, 2020)
New Study Shows Obese Children Need to Eat Fish to Raise their Omega-3 Index
A recent study from researchers in Canada aimed to determine whether long-chain polyunsaturated fatty acids (commonly referred to as omega-3 EPA and DHA) and fatty acid status relates to body composition in children with obesity.
The study was a cross-sectional analysis of 63 school age (6-13 years) children with obesity, but who were otherwise healthy, living in or near Montreal, Quebec. The study group was 48% female and 68% were pre-pubertal.
Dietary intake was measured through 3-day food diaries (two weekdays, one weekend day) the week after the baseline visit. The food intakes were reported by a parent or caregiver with instruction from a registered dietitian.
Blood was drawn from each child in the 12-hour fasted state, and the Omega-3 Index was the standard used to measure the amount of EPA and DHA in the red blood cells. The sum of the red blood cell EPA + DHA was expressed as a percentage of the total fatty acids.
The study authors concluded that lower omega-3 EPA and DHA status in children with greater adiposity is consistent with suboptimal intakes of omega-3 fatty acids and fish in the diet.
In other words, this study found children with obesity have a lower Omega-3 Index than healthy weight children. Also observed was a moderate inverse relationship between the Omega-3 Index, fasting insulin levels and Homeostatic Model Assessment for Insulin Resistance scores in children (5-12 years). The authors also advise that the role of excess dietary fat consumption in the cause of childhood obesity remains questionable.
As for the first conclusion, OmegaQuant’s Dr. Bill Harris, co-inventor of the Omega-3 Index, was not surprised by the results. He said, “The study’s findings are pretty obvious given the lack of omega-3 rich fish or supplements in obese kids’ diets, which is reflected in their low Omega-3 Index. Unfortunately, this sets them up for other illnesses as they grow older.”
Dr. Harris advises that a simple intervention like adding more fish, such as salmon, or a daily omega-3 supplement to kids’ diets could offer obese children protection against future health issues.
The authors agree, advising that “Consumption of EPA and DHA directly from foods and/or dietary supplements is the most practical way for humans to increase levels of these fatty acids in tissues.”
The body of research on the relationship between omega-3 and red blood cell measurements is inconsistent for children with obesity, according to the authors. But despite that, they believe studies such as theirs have laid the groundwork for future intervention trials to investigate the potential benefits of increasing EPA and DHA status on metabolic function, especially in a population with low baseline EPA and DHA status.
Small Study Finds Potentially Big Results for Omega-3s and Obesity in Children
Another recent study, this one from the Department of Pediatrics at the Yale School of Medicine, suggests that a lower ratio of omega-6 to omega-3 fatty acids improves, independent of weight loss, the metabolic phenotype of obese adolescents with fatty liver disease. Obesity is associated with an increased risk of fatty liver disease.
The study, published in The Journal of Nutrition, further found that response to this type of diet is modulated by a specific genotype, PNPLA3rs738409.
The 12-week single-arm unblinded study enrolled 20 obese children and adolescents (median age 13.3 years), with 17 still enrolled at the end of the study. After 12 weeks of dietary intervention, the hepatic fat fraction (HFF) decreased from baseline by 25.8%.
This result was achieved even as the study controlled for the potential confounding variables of weight loss or gain through caloric adjustments as needed and all participants were instructed to keep their physical activity level stable during the intervention.
The study team provided all needed dietary intake to participants and the food was measured and packaged each day by the Metabolic Kitchen of the Yale Center for Clinical Investigation. Compliance was assessed using simplified food records.
The intervention diet consisted of a low n-6 to n-3 PUFA radio of 4:1, and the macronutrient content was 50%-55% total daily calories from carbohydrate, 20% from protein, and 25-30% from fat, with saturated fat comprising 8-10% of daily total caloric intake and monosaturated and polyunsaturated fats each comprising 8-10% of daily total caloric intake.
The diet was rich in omega-3 fatty acids (e.g., fish and nuts) and although no supplements were used in the study, some foods were enriched with omega-3s.
According to the researchers, the study “has shown, to our knowledge for the first time, that a non-pharmacologic, food-based dietary intervention high in omega-3 and low in omega 6 polyunsaturated intake improves fatty liver disease in obese adolescents, and restores liver fat content to normal in one-third of participants, in the absence of weight loss.”
The authors noted several study limitations, including the small sample size, lack of control intervention, and whether the change in diet would be practical in the real world.
They also pointed out it is not yet determined whether the nutritional modification would be generalizable to a larger population.
Interestingly the authors identified another important limitation: the fact that the lipids were measured in the plasma, rather than in the red blood cell membrane. OmegaQuant believes the latter is the preferred method. Find out more here.
More Research Demonstrates Benefits of Omega-3s for Children
A study in the International Journal of Molecular Science noted that accumulation of DNA damage has been reported in people with obesity and is suggested to be involved in the development of obesity-related disease.
That makes our previous blog reporting on a study in the journal of Food & Function especially relevant because that research showed that children with higher levels of omega-3s EPA and DHA in their blood had less DNA damage than those who had lower levels.
The study out of Brazil looked at blood levels of several nutrients — omega-3s EPA and DHA, vitamin B12, beta-carotene and riboflavin—in a population of 140 healthy children and teens.
Data collection included body measurements, assessment of energy intake and blood sampling. Researchers also used single-cell gel electrophoresis (comet assay), which is the most widely used method for evaluating DNA damage. The goal was to verify associations between blood concentrations of vitamins and omega-3 fatty acids and DNA damage.
Of all the nutrients studied, the researchers found omega-3s were highly correlated with DNA damage in these children vs. the other nutrients. In other words, the more omega-3s in their blood, the less DNA damage there was. And given that DNA damage is connected to a wide variety of chronic diseases—such as heart disease, diabetes, cancer, etc.— researchers believe assessing omega-3 status could be a way to proffer protection.
So how do omega-3s protect DNA? According to researchers in this study, omega-3 EPA and DHA are substrates for the synthesis of pro-resolving mediators of inflammation that play a key role in the resolution and balance of the inflammatory process. Therefore, they can protect against DNA damage by mediating inflammatory pathways.
Omega-3s and Asthma in Children
The incidence of asthma has more than doubled over the last several decades. In fact, the American Academy of Asthma, Allergy & Immunology (AAAA&I) says childhood (pediatric) asthma is the most common serious chronic diseases in infants and children.
Children with obesity are especially prone to this condition.
A growing body of research suggests that getting enough omega-3 fatty acids during pregnancy and early life can impact the development of asthma in children. The connection between omega-3 fatty acids and asthma has been studied more in recent decades, driven by a rapid increase in this disease and the role that omega-3s play in conditions underpinned by inflammation.
Omega-3s and Autism
Autism is a complex disorder, with many levels of severity and manifestations of behavior and physical abnormalities. Previous studies have suggested a link between omega-3 fatty acids EPA and DHA and the prevalence of autism, and whether or not sufficient maternal intake of these nutrients can reduce the risk of this disorder in children.
More specifically, studies have suggested that these important fatty acids may have protective effects on autism spectrum disorder (ASD) in children.
The MARBLES study investigated whether maternal omega-3 intake at certain points in pregnancy, assessed by both questionnaires and biomarkers, is associated with risk of ASD and other non-typical development (non-TD) in the children. Food frequency questionnaires were used to estimate maternal omega-3 intake during the first and second half of pregnancy.
Evaluating omega-3 intake from questionnaires, researchers found that mothers consuming more omega-3 in the second half of pregnancy were 40% less likely to have children with ASD. In the third-trimester, however, researchers did not observe any statistical significance in relation to the risk of ASD.
Omega-3s and ADHD
Chances are you’ve heard of or may even know someone struggling with attention-deficit/hyperactivity disorder (ADHD), a brain disorder that makes it difficult to control impulses and be attentive for more than short periods of time. ADHD affects an estimated 8.4 percent of kids and 2.5 percent of adults, according to the American Psychiatric Association (APA).
Are omega-3s good for ADHD? There’s promising new evidence that says yes, these long-chain polyunsaturated fatty acids may play a valuable role in lowering the risk of ADHD in children should the mother consume enough of them during pregnancy.
Omega-3s are known to play a crucial role in the function of the central nervous system, particularly in the third trimester and are vital to baby’s brain development.
INFOGRAPHIC: 10 Reasons Every Pregnant Woman Needs Needs to Know Her DHA Level