Pleasurable behaviors reduce stress via brain reward pathways.

Individuals often eat calorically dense, highly palatable "comfort" foods during stress for stress relief. This article demonstrates that palatable food intake (limited intake of sucrose drink) reduces neuroendocrine, cardiovascular, and behavioral responses to stress in rats. Artificially sweetened (saccharin) drink reproduces the stress dampening, whereas oral intragastric gavage of sucrose is without effect. Together, these results suggest that the palatable/rewarding properties of sucrose are necessary and sufficient for stress dampening. In support of this finding, another type of natural reward (sexual activity) similarly reduces stress responses. Ibotenate lesions of the basolateral amygdala (BLA) prevent stress dampening by sucrose, suggesting that neural activity in the BLA is necessary for the effect. Moreover, sucrose intake increases mRNA and protein expression in the BLA for numerous genes linked with functional and/or structural plasticity. Lastly, stress dampening by sucrose is persistent, which is consistent with long-term changes in neural activity after synaptic remodeling. Thus, natural rewards, such as palatable foods, provide a general means of stress reduction, likely via structural and/or functional plasticity in the BLA. These findings provide a clearer understanding of the motivation for consuming palatable foods during times of stress and influence therapeutic strategies for the prevention and/or treatment of obesity and other stress-related disorders.

Age related macular degeneration--should your patients be taking additional supplements?

BACKGROUND: The use of over-the-counter complementary medicines and supplements is growing. Patients with age related macular degeneration (AMD) are likely to have heard of, or are possibly already taking, additional supplements that may increase their chances of retaining useful eyesight. OBJECTIVE: This article looks specifically at evidence regarding the effects of over-the-counter oral supplements such as antioxidants and omega-3 fatty acids on AMD. DISCUSSION: Diet manipulation and supplementation has a role to play in modifying the risk of disease progression in AMD patients. A combination of vitamins C and E, beta carotene, zinc oxide and cupric oxide has been shown to reduce the rate of visual loss in dry AMD. However, commercially available preparations do not always recommend the correct intake that would match levels found in clinical trials. Other carotenoids such as lutein and zeaxanthin may also be beneficial, intake of these can be increased by altering diet alone. Other useful dietary changes include reducing both animal and vegetable fats and increasing the consumption of fish and nuts.