Telomeres are very trendy in the research community. Like chia seeds and kale with hipster foodies. Telomeres are repetitive chains of amino acids attached to strands of your DNA. The longer your telomeres, the lower your risk of chronic disease and premature death, generally speaking.
The massive Nurses Health Study showed that women who ate a Mediterranean-style diet had the longer telomeres, which is good. That fits with other evidence of greater longevity and lower chronic disease rates in Mediterranean dieters.
To lose weight with the Mediterranean diet, check out my book, The Advanced Mediterranean Diet (2nd edition).