Lately, it seems that there is a constant stream of information in the news about eating more fruits and vegetables. Experts recommend five to nine servings per day. Study after study seems to prove that the more vegetables you eat, the lower your risk of cancer, heart disease, autoimmune disease, constipation, diabetes, and obesity will be. Some of the more noteworthy studies have been discussed in this column in the past.

Now that this idea is beginning to sink in, consumers are asking questions. This time we’ll address some questions that have come up about how to select fruits and vegetables to maximize their nutritional benefit. For years fresh was thought to be better that frozen. Sometimes this may be true, but you may be surprised at what frozen can offer. Care in selecting your produce can make the difference.

When shopping for fruits and vegetables variety is key. Always try to mix different fruits and vegetables into your diet. Every plant food has concentrations of different nutrients that are vital to life. In the past we’ve discussed how the different pigments in produce supply a host of health-protective phytochemicals. When shopping for fresh produce always select the brightest, most vibrantly colorful items.

Time and light are the biggest enemies of nutrients in produce. When produce gets old, colors fade and skins get wilted. This translates to lost nutrients, so steer clear of produce that doesn’t look good. The water-soluble nutrients like vitamin C and B vitamins are the most vulnerable. Experts say skinless vegetables like broccoli and greens suffer the most, while oranges apples and others produce with skins do better. (One surprising exception is the fat-soluble beta-carotene in carrots, which actually seems increase over time.)

If time is a problem for you select ready-to-eat, prepared produce like pre-mixed salads, peeled carrots or cubed fruit. These must be very fresh since some will lose nutrients even faster after preparation. Still, if it makes the difference between eating them or skipping them, go for it. When selecting salads, go for higher nutrient greens like romaine lettuce, or even better, mixed baby greens called mesclun. (Avoid the nutritionally useless iceberg lettuce if possible.)

When buying fresh produce try your best to buy certified organic products. This means they were grown without harmful chemical pesticides or fertilizers. They are not always available, but when they are they are worth the extra money. Most of the pesticides used on non-organic foods are carcinogenic or disruptive to hormone levels in the body. According to a 1999 Consumers Union study, the 10 most contaminated foods are peaches, strawberries, spinach, green beans, winter squash, apples, pears, grapes, tomatoes and celery. Always wash all produce well to reduce the pesticide residue.

Another option if your preparation time is limited is selecting frozen veggies. Believe it or not, frozen vegetables very often have higher nutritional value than fresh. That’s right, that means it may actually be better for you. (We’re talking about plain veggies here, not broccoli with hollandaise sauce.) This is because produce that is destined to be sold frozen is usually processed hours after being picked and quickly frozen. This preserves most of the delicate nutrients better. Many items in the “fresh” bin at the supermarket may actually have left the field more than a week ago.

Another reason frozen can be better than fresh is safety. Some items like frozen strawberries actually have one-fourth the pesticide residues of their fresh counterparts. Also, depending on the quality of sanitary conditions in the shipping and supermarket facilities, “fresh” produce can become contaminated with harmful bacteria. This is rarely a concern with frozen produce.

Frozen vegetables offer a wider year-round selection than the fresh bin at many supermarkets, making it easier to add that all-important variety to your diet. Also, since they are pre-cut and ready to go, busy people are more likely to eat them. And lastly, if you take into account the fact that you are not paying for stems, seeds or pits, frozen may actually cost less per pound.

Hopefully, this information will make it a bit easier to increase the amount of healthy fruits and vegetables in your diet. You can make the effort more fun by preparing vegetables with a little style. If you need ideas, buy a vegetarian cookbook. Boiling is boring…vegetables aren’t. While controversy in scientific studies is common, very rarely have we ever seen this fact controverted: eating more whole fruits and vegetables helps prevent disease and promote better health.