Nutrition and healthy ageing: calorie restriction or polyphenol-rich "MediterrAsian" diet?

Abstract

Diet plays an important role in mammalian health and the prevention of chronic diseases such as cardiovascular disease (CVD). Incidence of CVD is low in many parts of Asia (e.g., Japan) and the Mediterranean area (e.g., Italy, Spain, Greece, and Turkey). The Asian and the Mediterranean diets are rich in fruit and vegetables, thereby providing high amounts of plant bioactives including polyphenols, glucosinolates, and antioxidant vitamins. Furthermore, oily fish which is rich in omega-3 fatty acids is an important part of the Asian (e.g., Japanese) and also of the Mediterranean diets. There are specific plant bioactives which predominantly occur in the Mediterranean (e.g., resveratrol from red wine, hydroxytyrosol, and oleuropein from olive oil) and in the Asian diets (e.g., isoflavones from soybean and epigallocatechin gallate from green tea). Interestingly, when compared to calorie restriction which has been repeatedly shown to increase healthspan, these polyphenols activate similar molecular targets such as Sirt1. We suggest that a so-called "MediterrAsian" diet combining sirtuin-activating foods (= sirtfoods) of the Asian as well as Mediterranean diet may be a promising dietary strategy in preventing chronic diseases, thereby ensuring health and healthy ageing. Future (human) studies are needed which take the concept suggested here of the MediterrAsian diet into account.

Figure 1

Sirt1-mediated regulation of metabolism in different tissues according to [92]. In pancreatic β-cells Sirt1 represses the expression of UCP2, thereby increasing insulin secretion, and Sirt 1 also regulates FoxOs, thereby protecting the β-cells against oxidative stress. In the liver Sirt1 regulates gluconeogenesis by activating PGC-1α. In muscle cells Sirt1 activates both PGC-1α and FoxO, thereby influencing mitochondrial biogenesis, respiration, and fatty acid oxidation. ATP: adenosine triphosphate; FoxO: forkhead box protein O; PGC-1α: peroxisome proliferator-activated receptor-γ coactivator 1 alpha; UCP: uncoupling protein 2.

Figure 2

Sirt4 mediated amino acid metabolism according to [92]. ASSIS: amino acid-stimulated insulin secretion.

Figure 3

Important food items and their corresponding constituents in the Mediterranean, Asian, and so-called MediterrAsian diet.