Going Raw to Obtain it All?: The Effect of Cooking Vegetables on Nutrient content & availability

One of my favorite vegetable groups to recommend are the "leafy greens", and particularly, spinach. I tell my clients to buy frozen spinach and add it to omelets in the morning, or use it to bulk up soups or any meal. I also tell clients to keep a bag of frozen vegetables on hand at all times (I love the stir fry bags from Costco!). A lot of times people are surprised by the fact that I am recommending 1) frozen vegetables, and 2) heating/cooking the vegetable.


I understand that most people believe that eating raw and fresh produce is best... which it is. However, rarely do we consumers actually get the freshest produce. If you look at your piece of fruit, or the artichokes that just came in, they are most likely from some other continent. If they are actually from the US, they are most likely from California or somewhere far away. If the produce came from far way, obviously this means that thit couldn't have been picked today- it was probably picked several days (or weeks?) ago, put into cold storage, and shipped to your local store. So, I do recommend frozen vegetables because these are picked at the peak of ripeness and flash frozen to keep all their nutrients in.

Anyway, as far as cooking vegetables, certain types lose a lot of nutrients when you cook them in water, while others have nutrients that are made more intense and more bio-available (i.e: easier for your body to absorb) by cooking. However, it does depend on the type of vegetable, cooking method (microwaving, baking, steaming, boiling, roasting, grilling, etc.), and length of time the vegetable is exposed to heat and/or water. For example, spinach has many water-soluble vitamins and it is not recommended to boil spinach for more than one minute in order to obtain the most nutrients. However, for kale (another leafy green), it needs to be steamed for about 5 minutes for maximum nutrient availability. Lycopene (a phytonutrient) in tomatoes is made stronger by cooking down the tomatoes. So, my recommendation is to look up whatever vegetable you are going to prepare and determine the best way to cook it to preserve the most nutrients.

Final Thoughts: Don't go crazy thinking about your vegetables and how to cook them properly. For many people who don't eat any vegetables, it is much better to eat overcooked spinach than to have no spinach at all! Try to maximize the amount of veggies you eat during the course of the day by making 1/2 of your plate at lunch and dinner full of vegetables. If you only like cooked vegetables, then cook them! If you are eating a ton of veggies, you will most likely be getting enough of the critical nutrients your body needs, even accounting for nutrient losses through cooking.