**5. Neurohormetic phytochemicals**

Mediterranean diets rich in fibres, vegetables, fruits and olive oils are associated with reduced risk of cardiovascular disease and many neurological diseases. [32-34]Some effects are explained by antioxidative effects of different phytochemicals, but there is also evidence that some effects may be due to subtoxic effects of some neurotoxic molecules in the gut.

Hormesis is the paradoxical, stimulatory or beneficial action of toxins. Hormetic effects explain why, sometimes, low doses of a given toxic substance, or radiation, may induce beneficial effects while larger doses of the same substance or radiation are toxic to cells and organisms. [35, 36] Examples of endogenous molecules with neurohormetic actions are nitric oxide, carbon monoxide, glutamate and calcium. Examples of neuroprotective substances include alphatocopherol, lycopene, resveratrol (red grapes, red wine, peanuts and soy), sul-foraphanes (broccoli), catechins (green tea), allicin and allium (garlic), curcumin (turmeric) and hypericin (St John's Wort).

Hot spices may disturb sleep. Tabasco and mustard in the evening may reduce slow wave and reduce total time awake and increase time to fall asleep. The spicy food in the evening elevated body temperature during the first sleep cycle, which explains probably some of the effects of capsaicin on sleep. [37]
