Polyunsaturated fatty acid supplementation for ADHD? Fishy, fascinating, and far from clear

Omega-3 and Zinc supplementation as complementary therapies in children with attention-deficit/hyperactivity disorder

Objective:

The aim of this study is to evaluate the effect of zinc and omega-3 supplements as adjunctive drugs in the treatment of attention-deficit/hyperactivity disorder (ADHD) of children.

Methods:

This study is a randomized, double-blind clinical trial conducted on 150 children aged 6–15 years old that diagnosed as new cases of ADHD. Study subjects were evaluated for 8 weeks. Besides of drug of choice (methylphenidate) for the ADHD, patients received placebo in the control group (n = 50), zinc sulfate in second group (n = 50), and omega-3 (n = 50) in third group. Clinical improvement was checking by Conners’ Parent and Teacher Rating Scales before and in 2^nd, 4^th, and 8^th week of treatment. Results were analyzed with SPSS version 16 software.

Findings:

In this study, mean scores of Conners’ scale showed significant improvement during treatment in the zinc group compared to control group in children that affected to attention-deficit disorder subtype of ADHD (P = 0.02). Moreover, in omega-3 group, better clinical response was seen than other groups (P < 0.05). However, there was no significant difference between omega-3 group compared to placebo group in the mean scores of Conners’ scale (P = 0.89).

Conclusion:

Zinc supplementation accompanied by the main treatment significantly improves symptom of attention-deficit disorder subtype of ADHD. However, omega-3 supplementation was superior to zinc and placebo in the clinical improvement of ADHD.

Attention-deficit disorder associated with breast-feeding: a brief report

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) is one of the most common neurodevelopmental disorders that develop in children. In the United States and Canada, the prevalence is about 6%. The causes of ADHD are not known. ADHD, like autism, occurs mainly in boys aged 3-6, and there are some thoughts that both diseases may have a common mechanism.

METHODS

This study uses nutritional epidemiology linked to exclusive 6-month breast-feeding. The Centers for Disease Control and Prevention (CDC) has reported in 2003 and 2007 extensive studies on ADHD involving several million children in 50 states. The prevalence of ADHD in each state in 2003 or 2007 was compared to the average of exclusive 6-month breast-feeding from 2001 to 2004 or 3-month exclusive breast-feeding in 2007 in each of the 50 states. Several parameters, such as premature births, low birth weight, and very low birth weight, that had previously associated with ADHD were compared to ADHD incidence. Other parameters such as obesity, infant death rate, neonatal death rate, poverty, per capita income, and the percentage of individuals enrolled in the U.S. WIC (Women, Infants, and Children) program were also compared to ADHD incidence.

RESULTS

A highly significant inverse relationship of ADHD to exclusive 6-month and 3-month breast-feeding in 2007 was observed. Direct relationships were observed between premature births, low birth weight and very low birth weight, obesity, infant deaths, neonatal deaths, and ADHD.

INTERPRETATION

Breast milk contains components that appear to prevent ADHD.

Omega-3 fatty acid treatment of children with attention-deficit hyperactivity disorder: A randomized, double-blind, placebo-controlled study

BACKGROUND

Although several clinical trials have evaluated the impact of n-3 polyunsaturated fatty acid (PUFA) on patients with attention-deficit hyperactivity disorder (ADHD), changes in plasma PUFA composition were not always assessed following n-3 supplementation. Furthermore, no reports are available on the efficacy of n-3 PUFA in Canadian youth with ADHD.

OBJECTIVES

To determine fatty acid (FA) composition, and the efficacy and safety of n-3 PUFA supplementation on ADHD clinical symptoms in French Canadian primary school children.

PATIENTS AND METHODS

The Strengths and Weaknesses in ADHD and Normal Behaviors (SWAN) and Conners' questionnaires were used to assess changes in ADHD symptoms in 37 children (only 26 children completed the study from zero to 16 weeks). They were divided into two groups (A and B), and participated in a 16-week, double-blind, one-way, crossover randomized study. In the first phase, group A received the n-3 PUFA supplement and group B received n-6 PUFA (sunflower oil) as a placebo. During the second phase, group B received the active n-3 PUFA supplement that was continued in group A. FA composition and lipid profile were assessed during the phases of the study.

RESULTS

FA differences between groups were observed in the 26 patients. Supplementation with n-3 PUFA resulted in significant increases in eicosapentaenoic and docosahexaenoic acids in group A, while group B was enriched with alpha-linolenic, gamma-linolenic and homo-gamma-linolenic acids. The n-3 PUFA supplement was tolerated without any adverse effects. A statistically significant improvement in symptoms was noted based on the parent version of the Conners' questionnaire from baseline to the end of phase 1, and this amelioration continued from phases 1 to 2, although the latter changes from phases 1 and 2 were not statistically significant in any of the subscales except for the subscale measuring inattention in group B. The improvement was greater in patients from group A in phase 1 and in patients from group B in phase 2. A subgroup of eight patients (four in each group) displayed a statistically significant clinical improvement following the administration of the n-3 PUFA supplement, particularly for the inattention and global Diagnostic and Statistical Manual of Mental Disorders, Fourth edition, total Conners' subscales.

CONCLUSIONS

A subgroup of children with ADHD who used n-3 PUFA supplements achieved and maintained symptom control. The data of the present study also supported n-3 PUFA safety and tolerability, but limited changes were noted in the FA profile in French Canadians with ADHD.

Significance of long-chain polyunsaturated fatty acids (PUFAs) for the development and behaviour of children

omega-6 and omega-3 polyunsaturated fatty acids (PUFAs) play a central role in the normal development and functioning of the brain and central nervous system. Long-chain PUFAs (LC-PUFAs) such as eicosapentaenoic acid (EPA, C20:5omega-3), docosahexaenoic acid (DHA, C22:6omega-3) and arachidonic acid (AA, C20:4omega-6), in particular, are involved in numerous neuronal processes, ranging from effects on membrane fluidity to gene expression regulation. Deficiencies and imbalances of these nutrients, not only during the developmental phase but throughout the whole life span, have significant effects on brain function. Numerous observational studies have shown a link between childhood developmental disorders and omega-6:omega-3 fatty acid imbalances. For instance, neurocognitive disorders such as attention-deficit hyperactivity disorder (ADHD), dyslexia, dyspraxia and autism spectrum disorders are often associated with a relative lack of omega-3 fatty acids. In addition to a high omega-6 fatty acid intake and, in many cases, an insufficient supply of omega-3 fatty acids among the population, evidence is increasing to suggest that PUFA metabolism can be impaired in individuals with ADHD. In this context, PUFA imbalances are being discussed as potential risk factors for neurodevelopmental disorders. Another focus is whether the nutritive PUFA requirements-especially long-chain omega-3 fatty acid requirements-are higher among some individuals. Meanwhile, several controlled studies investigated the clinical benefits of LC-PUFA supplementation in affected children and adolescents, with occasionally conflicting results.

Essential fatty acids and attention-deficit-hyperactivity disorder: a systematic review

AIM

Essential fatty acids (EFAs), also known as omega-3 and omega-6 fatty acids, have been claimed to have beneficial effects as a treatment for attention-deficit-hyperactivity disorder (ADHD). Animal experiments have provided information about the role of EFA in the brain, and several mechanisms of EFA activity are well known. The current review provides an updated, systematic overview of the theory and use of EFA in ADHD.

METHOD

Clinical studies and review papers of EFA blood levels and EFA supplementation trials in children with ADHD were researched in the Medline PubMed database. Additional studies were found from the references of these reports.

RESULTS

Children with ADHD present lower levels of blood EFAs, and open-label EFA supplementation trials in ADHD raise EFA blood levels and improve symptoms of ADHD. Randomized controlled trials, however, have generally been unsuccessful in demonstrating any behavioural treatment effects.

INTERPRETATION

Current findings do not support the use of EFA supplements as a primary or supplementary treatment for children with ADHD.

Effect of fish oils containing different amounts of EPA, DHA, and antioxidants on plasma and brain fatty acids and brain nitric oxide synthase activity in rats

BACKGROUND

The interest in n-3 polyunsaturated fatty acids (PUFAs) has expanded significantly in the last few years, due to their many positive effects described. Consequently, the interest in fish oil supplementation has also increased, and many different types of fish oil supplements can be found on the market. Also, it is well known that these types of fatty acids are very easily oxidized, and that stability among supplements varies greatly.

AIMS OF THE STUDY

In this pilot study we investigated the effects of two different types of natural fish oils containing different amounts of the n-3 PUFAs eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and antioxidants on plasma and brain fatty acids, blood lipids, vitamin E, and in vivo lipid peroxidation, as well as brain nitric oxide synthase (NOS) activity, an enzyme which has been shown to be important for memory and learning ability.

METHODS

Sprague-Dawley rats were divided into four groups and fed regular rat chow pellets enriched with 5% (w/w) of butter (control group), a natural fish oil (17.4% EPA and 11.7% DHA, referred to as EPA-rich), and a natural fish oil rich in DHA (7.7% EPA and 28.0% DHA, referred to as DHA-rich). Both of the fish oils were stabilized by a commercial antioxidant protection system (Pufanox) at production. The fourth group received the same DHA-rich oil, but without Pufanox stabilization (referred to as unstable). As an index of stability of the oils, their peroxide values were repeatedly measured during 9 weeks. The dietary treatments continued until sacrifice, after 10 days.

RESULTS

Stability of the oils varied greatly. It took the two stabilized oils 9 weeks to reach the same peroxide value as the unstable oil reached after only a few days. Both the stabilized EPA- and DHA-rich diets lowered the triacylglycerols and total cholesterol compared to control (-45%, P < 0.05 and -54%, P < 0.001; -31%, P < 0.05 and -25%, P < 0.01) and so did the unstable oil, but less efficiently. Only the unstable oil increased in vivo lipid peroxidation significantly compared to control (+40%, P < 0.001). Most of the fatty acids in the plasma phospholipids were significantly affected by both the EPA- and DHA-rich diets compared to control, reflecting their specific fatty acid pattern. The unstable oil diet resulted in smaller changes, especially in n-3 PUFAs. In the brain phospholipids the changes were less pronounced, and only the diet enriched with the stabilized DHA-rich oil resulted in a significantly greater incorporation of DHA (+13%, P < 0.01), as well as total n-3 PUFAs (+13%, P < 0.01) compared to control. Only the stabilized DHA-rich oil increased the brain NOS activity (+33%, P < 0.01).

CONCLUSIONS

Both the EPA- and DHA-rich diets affected the blood lipids in a similarly positive manner, and they both had a large impact on plasma phospholipid fatty acids. It was only the unstable oil that increased in vivo lipid peroxidation. However, the intake of DHA was more important than that of EPA for brain phospholipid DHA enrichment and brain NOS activity, and the stability of the fish oil was also important for these effects.

Lipid profile, fatty acid composition and pro- and anti-oxidant status in pediatric patients with attention-deficit/hyperactivity disorder

Attention-deficit/hyperactivity disorder (ADHD) is the most prevalent behavioral disorder in children and the pathophysiology remains obscure. In addition to the pharmacotherapy, which is the primary treatment of ADHD, nutritional intervention may have a significant impact on ADHD symptoms. We studied lipid and lipoprotein profiles, fatty acid (FA) composition, and oxidant-antioxidant status in 37 pediatric ADHD patients and 35 healthy control subjects. Our results show that plasma triacylglycerols and phospholipids were lower, whereas free cholesterol, HDL, and apolipoprotein A-I were higher in ADHD patients compared with controls. The proportion of plasma EPA and DHA was higher, but that of oleic and alpha-linolenic (ALA) acids was lower. As expected from these findings, the proportions of both total saturates and polyunsaturates fatty acids (PUFA) were higher and lower, respectively, in ADHD patients than in controls, which led to a significant decrease in the PUFAs/saturates ratio. On the other hand, the ratios of eicosatrienoic acid to arachidonic acid and of palmitoleic acid to linoleic acid, established indexes of essential fatty acid (EFA) status remained unchanged revealing that EFA did not affect ADHD patients. Similarly, the activity of delta-6 desaturase, estimated by the ratio of 18:2(n-6)/20:4(n-6), was found unaffected, whereas ALA/EPA was diminished. Lessened lipid peroxidation was noted in ADHD subjects as documented by the diminished values of plasma malondialdehyde accompanied by increased concentrations of gamma-tocopherol. In conclusions, significant changes occur in the lipid and lipoprotein profiles, as well as in the oxidant-antioxidant status of ADHD patients, however, the FA distribution does not reflect n-3 FA deficiency.