Investigators in Spain randomized 7447 people at high risk for cardiovascular disease to one of three diets: a Mediterranean diet supplemented with extra-virgin olive oil, a Mediterranean diet supplemented with nuts, or a control diet for which people were advised to lower their intake of dietary fat.

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This diet was supplemented with fresh fish caught as they traveled, including tuna and shark.

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The raft stood up to Pacific storms and Mr Heyerdahl and his friends supplemented their diet with algae strained through cloth.

ECONOMIST: Thor Heyerdahl | The

Vitamin C may need to be supplemented in some cases if not enough is consumed in the diet.

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