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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Calorie restriction increases longevity through -
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The correct answer is  Siuins are a family of proteins that play a role in aging by regulating cellular health. They're responsible for critical biological functions like DNA expression and aspects of aging. However, siuins can only function in the presence of NAD+, nicotinamide adenine dinucleotide, a coenzyme found in all living cells. Ref Harrison 20th edition pg 78