re: Science debates anti-aging claims
1000 calories a day would be a 50% reduction of calories from an average diet of say 2000 calories a day. Proponents of calorie-restricted, high nutrition diets suggest 30% lower, or about 1700 calories a day. Remember too these are required to be diets high in nutrients.
The idea of calorie restriction for reducing aging is well proven in every animal group it's been tested on. Just as important is that it seems to also reduce the incidence of life threatening age-related diseases such as cancer and heart disease.
Bob Clark