A recent meta-analysis of 6 prospective cohort studies, which included more than 223,000 people, found that:1"Increasing daily intake of green leafy vegetables could significantly reduce the risk of type 2 diabetes."The reduction in risk was modest, just 14% for consuming a little over a serving a day. And the benefit was seen specifically with green leafies, not with vegetables on the whole, with fruit, or with fruit and vegetables combined.
Green leafy vegetables in these studies included spinach, kale, lettuce, and other greens. Had the definition of "green leafy vegetables" been broad enough to include other members of the cabbage and lettuce families, and green herbs such as parsley, dill, and fennel, there might have been a more pronounced benefit, suggest the authors.
Possible mechanisms for the benefit include omega-3 fatty acids, magnesium, and numerous antioxidant compounds all of which are found in green vegetables and all of which have been linked to a lower risk of diabetes or insulin resistance on their own.
1 Fruit And Vegetable Intake And Incidence Of Type 2 Diabetes Mellitus: Systematic Review And Meta-Analysis, British Medical Journal, August 2010
