Influencia de la suplementación con vitamina D, omega 3 o el uso de una dieta libre de gluten y caseína en el comportamiento de niños y niñas con trastorno del espectro autista / Influence of the vitamin D, omega 3 supplementation or the use of a gluten and casein free diet in the behavior of boys and girls with autism spectrum disorder

La prevalencia de trastorno del espectro autista ha ido en aumento, sin embargo, en Chile no existen lineamientos nutricionales acerca del posible tratamiento de la condición. Es por ello que el objetivo de esta revisión fue analizar la evidencia actual en relación al uso de una dieta libre de gluten y caseína, suplementación de vitamina D y omega 3 y su impacto en el comportamiento de niños/as con trastorno del espectro autista. Hay evidencia con resultados en torno a los beneficios de la suplementación con vitamina D debido a su carácter neuroprotector y su función neuromuscular. A su vez, la evidencia con omega 3 (DHA) es estadísticamente significativa para irritabilidad, hiperactividad, letargo, comportamiento estereotipado, conciencia social, comunicación y disminución de la severidad del autismo. Respecto a la dieta libre de gluten y caseína lo observado es que no existe evidencia que respalde los beneficios que esta exclusión entregaría. Aún falta evidencia para declarar un manejo nutricional específico para el tratamiento de los síntomas gastrointestinales y de comportamiento, más allá de la suplementación con aquellos micronutrientes en déficit.

The prevalence rate of autism spectrum disorder has been increasing, however, in Chile there are no nutritional guidelines about the possible treatment of the condition. That is the reason why the aim of this review is to analyze the current evidence regarding the use of a gluten and casein free diet, vitamin D and omega 3 supplementation and its impact in the behavior of children's with spectrum disorder autistic. There is evidence based on significant results regarding the benefits of vitamin D supplementation due to its neuroprotective character and neuromuscular function. At the same time the omega 3 evidence is statistically significant in the diminution of irritability hyperactivity, lethargy, stereotypical behavior, severity of autism and increase of social consciousness and communication. Regarding the gluten-free and casein-free diet, what was observed is that there is no evidence to support the benefits that this exclusion would provide. The evidence has not been conclusive to declare a specific nutritional management for the treatment of gastrointestinal and behavioral symptoms, beyond supplementation with those micronutrients in deficit.

Can red flowers be conspicuous to bees? Bombus dahlbomii and South American temperate forest flowers as a case in point.

It has been argued that trichromatic bees with photoreceptor spectral sensitivity peaks in the ultraviolet (UV), blue and green areas of the spectrum are blind to long wavelengths (red to humans). South American temperate forests (SATF) contain a large number of human red-looking flowers that are reported to be visited by the bumblebee Bombus dahlbomii. In the present study, B. dahlbomii's spectral sensitivity was measured through electroretinogram (ERG) recordings. No extended sensitivity to long wavelengths was found in B. dahlbomii. The spectral reflectance curves from eight plant species with red flowers were measured. The color loci occupied by these flowers in the bee color space was evaluated using the receptor noise-limited model. Four of the plant species have pure red flowers with low levels of chromatic contrast but high levels of negative L-receptor contrast. Finally, training experiments were performed in order to assess the role of achromatic cues in the detection and discrimination of red targets by B. dahlbomii. The results of the training experiments suggest that the bumblebee relies on achromatic contrast provided by the L-receptor to detect and discriminate red targets. These findings are discussed in the context of the evolutionary background under which the relationship between SATF species and their flower visitors may have evolved.