3.4.1 Pharmaceuticals or nutraceuticals?
Nutraceuticals refers to the use of food supplements or herbal remedies for health purposes. For example, certain ingredients of the herb St John's Wort can be as effective in managing depression as conventional anti-depressants, with fewer negative side effects (Greeson et al., 2001). However, research also shows that this supplement can interact negatively with some commonly prescribed drugs, such as the contraceptive pill. This highlights the need for:
proper research into food supplements and herbal remedies;
consulting a medical practitioner before taking any of the supplements.
Similarly, doctors sometimes ‘prescribe’ vitamins and minerals (e.g. vitamin B6 for depression, poor concentration or memory problems). Evidence has also emerged that supplements of fish oil, which contains certain highly unsaturated omega-3 fatty acids, may help to reduce the symptoms of serious mood disorders (Stoll et al., 1999). As discussed earlier, deficiencies in highly unsaturated fatty acids are also suspected of playing a part in behavioural and learning problems like ADHD, dyslexia and dyspraxia.
Even apparent evidence of benefits does not mean that the treatment is really addressing the underlying problem. For example, sleeping pills may render someone unconscious, but can we really say that this is addressing the underlying problem? You may ask: ‘does it matter if we don't know how something works, as long as it works?’ The answer depends on a careful evaluation of both the costs and the benefits associated with a particular treatment. However, even if a treatment appears to ‘work’, it can still be difficult or impossible to know whether the benefits observed result from the treatment. The problem of evaluating interventions, be they biological, cognitive or behavioural, is discussed in Section 3.5.
As we saw in Section 2, we still know comparatively little about the physical brain differences that may contribute to developmental dyslexia, and what we do know suggests limited scope for direct biological interventions. Related conditions such as ADHD are often treated using drugs, but there has been little investigation of possible biochemical contributions to dyslexia. However, as discussed, there is some evidence of deficiencies in certain highly unsaturated fatty acids, and case studies suggest that nutritional therapy may be helpful in some cases (see Box 15). Large-scale double-blind trials should soon reveal whether dietary supplementation may be of more general benefit in the management of dyslexia.
Box 15: A biochemical approach to dyslexia (Baker, 1985)
This report describes the case of a boy diagnosed with dyslexia, for whom biochemical testing revealed various imbalances. Correcting these with nutritional supplements led to clear improvements in his schoolwork. His story illustrates the importance of treating the individual child rather than the apparent problem of his dyslexia (which had not responded to conventional remedial teaching methods).
Deficiencies in certain fatty acids were considered the single most important factor in this case, but some vitamins and minerals were also lacking. Furthermore, to anyone familiar with the signs, this child's fatty acid deficiency was evident from simple observation (although biochemical testing was needed to confirm it).
Michael had very dry, patchy, dull skin. Like a matte finish on a photograph, his skin, as well as his hair, failed to reflect light with a normal lustre. His hair was easily tousled and when pulled between the fingers it had a straw-like texture rather than a normal silky feel. He had dandruff. The skin on the backs of his arms was raised in tiny closed bumps like chicken skin. His fingernails were soft and frayed at the ends. All of these findings point to an imbalance of fatty acids.
(Baker, 1985, p. 583)
This biochemical approach apparently angered some specialists, who took the view that ‘Nutrition has nothing to do with dyslexia’. However, as the author notes:
Improvement in Michael's school work coincided with the return of normal lustre and texture to his skin and hair. If he had been a cocker spaniel his family would have accepted the connection between his ‘glossier coat’ and better disposition more readily. The timing was convincing. Although it is never enough to establish ‘proof’ in a given person, Michael was convinced. He saw and felt the changes together, and he understood the idea behind the work we did with him. With a twinkle in his eye, he told his grandmother that dandruff had been the cause of his dyslexia.
(Baker, 1985, p. 583)
The doctor emphasised that he was simply treating the individual child, and did not regard dyslexia as any kind of ‘disease’. Instead it was the non-medical specialists who seemed pre-occupied with the ‘dyslexia’ label. Recall too our discussion of ‘explanations’, where we saw that a proper understanding of any psychological problem requires an appreciation of three levels – behavioural, cognitive and biological, as well as the way that environment (in this case diet) can impact on each of these. This report also shows the value of a well-documented single-case study, although randomised controlled trials are necessary to provide unequivocal evidence of benefits from biochemical treatments.
Some visual treatments, such as covering one eye when reading, have shown benefits in double-blind trials (Stein et al., 2000). However, this kind of specialist treatment is only appropriate for children who have particular visual deficits, and it requires proper professional supervision. Others, such as using coloured lenses or overlays for reading, are popular amongst some people with dyslexia and lead to improvements in reading ability in open studies (Sawyer et al., 1994), but as yet there is limited evidence from placebo -controlled studies to suggest that they are effective (Francis et al., 1992). A few other unconventional treatments for dyslexia are widely advertised by private clinics as ‘based’ on biological evidence, but have no reliable evidence of their efficacy. One unorthodox approach that has support from randomised, double-blind, placebo-controlled trials involves special physical exercises designed to improve aspects of motor coordination thought to reflect neurological immaturities in dyslexia (McPhillips et al., 2000). Benefits to physical coordination, reading and attention were reported.
Box 16: Definitions
Placebo: Any therapy that is used for a specific symptom or disease, but which is actually thought to be ineffective for that purpose. A placebo is usually employed in clinical trials for comparison with the ‘active’ treatment under study. A study with no placebo is an ‘open study’.