Dr. Jie Zhu, an assistant professor at Texas State University in nutrition in food, found an association between an increased amount of these vitamins and a reduction in metabolic syndrome.

Folate: Dark green leafy vegetables, broccoli, Brussels sprouts, citrus fruits, melons, strawberries, bananas, papaya, beets, avocado, peas, chickpeas and kidney beans, nuts and seeds, and liver.

B6: Poultry, pork, tuna and salmon, carrots, potatoes, bananas, dairy products such as milk and cottage cheese, peanuts, avocado, chickpeas, and eggs.

This study doesn't make recommendations, but Zhu says, "we want to convey messaging to pay more attention to these foods," he said.

People also can ask their primary care doctor to order a blood test to check the levels of these vitamins to make sure they are getting enough.

Your doctor might advise a supplement after testing your blood biomarkers and knowing how much of a vitamin you might need to make up the difference in what you are not getting through your diet.