Can Calorie Restriction Extend Human Lives?
It is still a question that humans can benefit from calorie restriction the way animals have. Among researchers widely believed the fact that calorie restriction diets trigger a survival mechanism in animals with a short life span, such as rodents, that allows them to outlive food shortages. If people have this adaptation remains to be seen.
Short trials of calorie restriction diets in people have shown some benefit.Those undergoing calorie restriction, whether through a restricted diet only or through a combination of diet and exercise, typically have seen positive changes in their:
• Blood pressure
• Blood sugar
• Body fat percentage
• Cholesterol levels
• Heart rate
• Weight
Whereas these are all healthy changes that may reduce the risk of chronic diseases, such as heart disease, it isn't clear whether these changes translate to a longer life span for humans.
In spite of the benefits, researchers have also identified risks of calorie restriction diets, including:
• Reduced bone density
• Loss of muscle mass
• Anemia
• Memory loss
• Dizziness
• Depression
Researches of people, who are severely malnourished, such as people with anorexia, show that getting inadequate amounts of vitamins and nutrients can lead to serious complications, such as heart failure and death.
Results have shown that people with the lowest range body mass index (BMI) scores have a higher risk of death than do those with scores considered normal. Though these studies aren't perfect — they don't take other important factors into consideration, such as undiagnosed cancer or other serious illnesses that may have caused weight loss. Nevertheless the results do give reason to be cautious when considering calorie restriction.
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