The Great Veggie Debate: Raw, Cooked, Fresh, Frozen or Canned?
A question we often get in our office, “which veggie provides the BEST nutrition?”. We’ve heard it all, from carrots are too high in sugar (not true), and veggies lose all of their nutrition when cooked (also not true). So, what is the best way to approach your veggies to get the absolute best benefit? The truth is that your number one priority should be getting veggies in regularly. Period. If the cost of fresh veggies is prohibitive, buy canned or frozen! If you’re not eating them, you’re not getting any of the nutritional benefits including vitamins, minerals, fiber, antioxidants, and am impact on your satiety (aka fullness).
The Fresh vs. Frozen Debate
The reality is that frozen fruits and veggies often times contain higher vitamin and mineral contents than fresh. The production of frozen produce includes leaving it on the vine for a longer period of time before picking, preserving and freezing. So, the nutrition of the veggie has more time to mature than it’s counterpart. Plus, if you have a week where you end up dining out more than expected or you have unexpected travel, you can come home and pick up where you left off with veggie prep! Frozen tends to create less food waste, but you will notice a difference in the texture of the veggie once cooked.
For fresh produce, often times they’re picked early to allow time for transport to stores. This is why bananas, for example, are usually green in stores. Picking early decreases time on the vine and can reduce nutrition slightly. Plus, the longer a veggie sits on store shelves, the more it oxidizes. Exposure to oxygen/air alone can cause changes in the nutrient composition of your produce.
*Take away message: Eat what you enjoy and will use regularly. Nutrition between the two is not significantly different!
Cooked vs. Raw
The processing of any vegetable causes slight changes in the nutrition composition. Cutting, steaming, boiling, frying, roasting, and even just oxygen exposure (which is unpreventable) causes changes to the nutrition composition of veggies. Cooking makes it easier for our body to break down foods in the digestive system, while raw can be very convenient when we are on-the-go. There is no straight-forward answer to whether cooked or raw is better because both can provide benefits.
Cooked veggies have been shown to be higher in free-radical fighting antioxidants that protect the body from diseases of cellular damage, like cancer. Lycopene (found in tomato products) is actually enhanced with cooking. Raw tomatoes don’t provide a significant amount of this antioxidant, but cooked tomato sauce does. Boiling seems to be one of the best methods to bring out this antioxidant specifically. On the other hand, cooking can destroy other nutrients, like the highly unstable vitamin C. Cooking in water (i.e. boiling) can leach some water soluble vitamins like thiamin and riboflavin while deep frying is the least recommended cooking method as it increases free radicals in the body due to the constant oxidation of the oil at high temperatures.
*Take away message: Veggies contain varying levels of nutrients (some higher and some lower) depending on their cooking method. It’s best to eat what you like with a variety of cooking methods to achieve 4-5 veggie servings daily. Keep intake of deep fried veggies low.
Organic vs. Non-organic
Is organic produce worth the extra cost? It depends on why you’re choosing it. . . Recent research suggests that nutrient content of organic veggies may be slightly higher than non-organic growing techniques, but not significantly so that you are “missing out” if you’re not buying organic. Pesticide exposure is another concern amongst the general population. When farmers spray pesticides on crops, some residue can be left on the peel/skin of the veggie. Both organic and non-organic veggie products have shown to have pesticide residues, due to airborne contamination from traditional farming practices. Washing your veggies well can reduce any exposure to these, and peeling the skin off lowers pesticide intake the most. However, when you peel off the skin, you will lose nutrient density of the veggie. Also, research has not currently shown negative impacts from pesticide exposure on veggies.
Perhaps the most confusing part for consumers is the controversy around GMOs in veggie production. GMO produced crops have not shown negative health impacts in current research, and they can actually reduce the need for traditional pesticide use. However, GMO crops are considered non-organic, therefore it can be difficult to tell the difference between those treated with pesticides or without. If you are specifically choosing organic foods to lower pesticide intake, there may be non-organic foods that are actually similar to their organic counterparts in pesticide exposure.
*Take away message: Cost should not deter you from eating veggies. Whether you’re choosing organic or non-organic, you are increasing your nutrition density and adding health-protecting antioxidants. Perhaps one of the best (and cheapest) methods is to have your own small garden for veggies used frequently, and buy from reputable, local sources for others when you can.