By Brooke Douglas. Vegetables are an essential part of a healthy, well-balanced diet and are the body’s last defense mechanism against diseases and illnesses. They are low in fat and calories, cholesterol free, and excellent sources of vitamins, minerals, and dietary fiber. Furthermore, they are rich in antioxidants or disease-fighting plant substances that protect against many health conditions, including cancer. But which type of vegetables is best? Do fresh, frozen, or canned vegetables contain more vitamins?
Garden fresh vegetables People assume that fresh vegetables are the healthiest choice, because they are not processed. Think again. This is true if you are buying produce from a local farmers’ market or picking vegetables directly out of the garden, but maybe not the case if you buy vegetables from a grocery store or purchase produce grown in another state or country.
The nutritional content of fresh vegetables depends on various factors, including seasonality and availability in the region. Many vegetables travel long distances to end up in the produce section of the local grocery store. When vegetables are shipped across several states, they are exposed to extreme light, heat, and temperature conditions, which can cause a loss of important nutrients, such as thiamine and vitamins A and C. Many fresh vegetables that travel many miles by truck or boat are harvested before they reach peak ripeness, so vitamins and nutrients have not had the time to reach complete potency. The produce still may show outward signs of ripening, but the vegetables will never have the same nutritional composition as fully developed plants.
From farm to fork It is estimated that much of the food consumed in the United States travels an average of 1500 miles from the farm to your kitchen table. One step you can take is to get a seasonal guide to local fresh produce, which is available from Washington state’s Department of Agriculture. However, from late October until early April, the only local fresh produce available in the northern regions of North America and in the northern latitudes of the world comes from the root vegetable, cabbage, onion, or squash families. If you want other types of fresh produce at this time of year, you can freeze or can your own when vegetables are at peak flavor and in season. In order to do so, you need canning and freezing equipment, as well as knowledge of storage methods and food safety.
Here is a better, easier alternative. The simple act of pushing your grocery cart through the frozen and canned vegetable section of your food market can help improve your nutrition and health! Frozen produce is sent directly from the fields and orchards where it is grown to a processor near the field. After produce is frozen or canned, it is preserved and stored at the processor before distribution in a large bulk shipment. Perishable fresh produce, on the other hand, needs to get to its destination rapidly and is shipped in smaller quantities and great distances, especially during the off-season. Fresh produce is shipped fast enough to prevent damage and spoilage, but its nutritional value may suffer. In fact, loss of vitamins and minerals in fresh vegetables is perhaps more significant than originally thought, according to study findings by Joy Rickman and colleagues published in the Journal of the Science of Food and Agriculture. The longer vegetables are in transition, the more nutrients are oxidized into the air. The average time frame from farm to your fork is about 10–14 days. In contrast, produce that is frozen and canned sits only a couple of hours before its freshness and nutrients are sealed in by the freezing or canning methods.
In order to ensure that you receive the full spectrum of vitamins and minerals from your fresh produce choices, choose produce directly from your garden or local farmers’ markets during the summer and fall harvest. But what if the shelves in the produce aisle are bare in the late fall and winter? What if you cannot always purchase the fresh selection, whether because of cost, season availability, spoilage risk, or taste preferences? Should you head to the freezer case to buy bags of frozen vegetables? Absolutely! Many scientific studies indicate that frozen vegetables are just as healthy, if not better in some instances, than the fresh selection.
The freezer section In 1998, the US Food and Drug Administration confirmed that frozen produce provides the same essential nutrients and health benefits to the body as its fresh counterpart. Frozen produce is nothing more than fresh produce that is blanched (cooked for a short time in boiling water or steamed) and then frozen within hours after the harvesting time. In addition, frozen vegetables are processed at their peak in terms of freshness and nutrition.
In an article in Eating Well magazine, Gene Lester, PhD, a plant physiologist at the US Dept of Agriculture’s Agricultural Research Center, Weslaco, TX, notes that while canned vegetables tend to lose many nutrients during the preservation process, frozen vegetables may be even more healthful than some of the fresh produce sold in grocery stores.
So, fresh vs frozen? The answer is frozen, that is if the fresh produce is traveling a long distance during off season and also if you do not plan on eating the vegetables quickly after buying them.
Straight out of the can The method used for canning produce is somewhat different than frozen, and in some instances, this can affect the nutritional content. Canned vegetables tend to lose some of their vitamin C in the high-heat temperature ranges used for canning. Similar to the frozen process, in the canning technique, the vegetables are picked at peak ripeness, blanched (this time for longer duration and with somewhat increased nutrient loss for heat-sensitive compounds, compared to the frozen method), and then canned. Salt is added to many canned vegetables to preserve flavor and prevent spoilage on the shelves in the stores and your homes. These additions can take a very healthy vegetable and make it less desirable than its fresh or frozen variety.
Nutrition Facts labels Check the sodium content on the Nutrition Facts labels, and buy vegetables with the key terms “no added salt” or “low sodium” printed on the label. Buy vegetables that do not contain added butter or cream sauce. When you buy canned vegetables, rinse them to get rid of some of the salt. When choosing frozen vegetables, make sure the only ingredients listed are the type of vegetables you intend to purchase. Boiling vegetables also releases nutrients, so boil them only for a very short time. Steaming is best!
Nutritional comparison between fresh, frozen, and canned vegetables By the time the produce is eaten, fresh, frozen, and canned vegetables may have few differences in nutritional value, depending on the handling and processing methods used after harvest. Each has the same carbohydrate, fat, and protein content as the product prior to picking the crop. While loss in water- and fat-soluble vitamins does vary depending on the processing method used after harvest, you can rest assured that the majority of frozen and canned (without preservatives) fruits and vegetables are just as healthy for your family as the fresh variety. In fact, you might try choosing a mix of fresh, frozen, and canned produce in order to help your family more easily, inexpensively, and creatively enjoy the nine or more servings per day of fruits and vegetables recommended by the Center for Disease Control and Prevention without sacrificing nutrition.
The bottom line Summer and early fall is the best time of year to visit local farmers’ markets or your own garden for fresh produce. However, during the rest of the year, it is important to continue eating vegetables, whether fresh, frozen, or canned. The average American eats only one third of the recommended daily intake of five to nine servings of vegetables per day.
Decide whether you want fresh, frozen, or canned vegetables—they will all provide you with the essential vitamins, minerals, and nutrients your body needs to function. Try to add vegetables into your meals daily to keep your body healthy and prevent diseases, whether you pick them straight from your backyard garden, get them at the farmers’ market or from your store’s produce section, grab them out of your freezer, or pull them off your kitchen shelf!
If you were glued to reading this entire article that means nutrition is important to you and your family’s health. Did you know that most insurance companies allow numerous visits with a Registered Dietitian? Let one of the nutrition experts at Nutrition Authority help coach you towards better health! There are now three locations to serve you – Renton, Puyallup and Tacoma. Consults are available from 7:00 am to 8:30 pm Monday through Friday. Weekend times are available twice monthly.
Contact Brooke at www.NutritionAuthority.com if you would like to meet with an R.D.!
References: American Council on Exercise. How much difference is there in nutritional value between fresh and frozen fruits and vegetables? Available at: http://www.acefitness.org/blog/859/how-much-difference-is-there-in-nutritional-value. Accessed April 11, 2012.
FitDay. Vitamins in veggies: fresh vs. canned vs. frozen. Available at: http://www.fitday.com/fitness-articles/nutrition/vitamins-minerals/vitamins-in-veggies-fresh-vs-canned-vs-frozen.html. Accessed April 11, 2012.
Gorman RM. Fresh vs. frozen vegetables: are we giving up nutrition for convenience? Available at: http://www.eatingwell.com/nutrition_health/nutrition_news_information/fresh_vs_frozen_vegetables_are_we_giving_up_nutrition_fo. Accessed April 11, 2012.
Hitti M. Canned fruits, veggies healthy, too: some processed produce more nutritious than fresh. Available at: http://www.webmd.com/food-recipes/news/20070316/canned-fruits-veggies-healthy-too. Accessed April 11, 2012.
Jones HK. Fresh vs. frozen: choosing your fruits and vegetables. Available at: http://www.healthcastle.com/veggies_fresh_frozen.shtml. Accessed April 11, 2012.
Levin M. Fresh versus frozen or canned: how to choose your fruit and vegetables. Available at: http://www.age-well.org/fresh-versus-frozen-fruit-vegetables.html. Accessed April 11, 2012.
Rickman JC, Barrett DM, Bruhn CM. Executive summary: nutritional comparison of fresh, frozen, and canned fruits and vegetables. Available at: http://www.mealtime.org/uploadedFiles/Mealtime/Content/ucdavisstudyexecutivesummary.pdf. Accessed April 11, 2012.
Tufts Medical Center. How far has your food traveled? Available at: http://www.tufts-nemc.org/apps/HealthGate/Article.aspx?chunkiid=13904. Accessed April 14, 2012.