Most Nutritious Way to Cook Vegetables
In today’s health conscious society, its common knowledge that eating vegetables is a vital ingredient to a healthy body. What the most nutritious way to cook vegetables though and why, is still a bit of a mystery to us common folk and something that isn’t even generally considered.
The reason it is recommended that vegetables from a part of our daily diet is that they are nutritionally rich, packed with essential vitamins and minerals and as we learned in the previous blog ( Why are Vegetables Healthy ), they are also loaded with phytonutrients which have been shown to be powerful antioxidants and may protect from various cancers and diseases.
It stands to reason that we would want to make sure that we are taking full advantage of what they have to offer, but unknowingly you may be cooking the vegetables incorrectly resulting in the loss of nutrients or at best, diminishing the levels of these nutrients.
With the help of this study “Effects of Different Cooking Methods on Nutritional and Physicochemical Characteristics of Selected Vegetables” , I am going to break down 3 different cooking methods, when you should be using them and why, to try and figure out what the best way to cook vegetables is to insure you maximum their potency.
In the study, 3 of the most common cooking methods used by the Italian population (boiling, steaming, and frying) were used to test how each method affected the phytochemical contents (i.e., ascorbic acid, carotenoids, polyphenols, and glucosinolates) and total antioxidant capacities of three vegetables (carrots, courgettes, and broccoli), with some very interesting results.
Boiling
Boiling is the most common method used to cook vegetables but may not be the ideal way to cook your vegetables especially if they contain water-soluble vitamins. When immersed in water and boiled, the vitamins in these vegetables are leached into the water and is the reason the water is colored after you have boiled vegetables in it. Unless you intend to make a soup or broth with this water you will be missing out on some of the nutritional benefits you could have had if cooked the right way. There is a school of thought suggesting that if the boiled vegetables are not organic, nitrates and pesticides from fertilizers can end up in the water so it could be best to discard the water all together.
Vitamin C (ascorbic acid) is one of these water-soluble vitamins. This vitamins can’t be stored in the body, resulting in us having to consume it on a regular basis through our diet. It plays a vital role in skin and bone health and is one of many antioxidants which can protect against free radicals which are suggested to be responsible for various cancers and heart disease. Consuming vitamin C also increases the amount of iron our body can absorb from vegetables and another reason to make sure that this vitamin is not wasted through the cooking process.
Glucosinolates are another water-soluble compounds found in dark green leafy vegetables such as broccoli which had a significant decrease in this cancer fighting compound when boiled.
It’s not all bad news though when it comes to boiling as there are exceptions.
Boiling, for example better preserved the antioxidant compounds, particularly carotenoids for all 3 vegetables but in the case of carrots, there was even an increase of 14% of this powerful antioxidant that fights oxidative stress within the body and helps to reduce inflammation.
As expected, the water-soluble ascorbic acid had a massive reduction in concentration of nearly 50% in broccoli when boiled. Interestingly though, boiling had very little effect on this compound in courgettes and only (−9%) in carrots.
Steaming
Steaming vegetables is a popular choice among the health conscious as this method doesn’t involve cooking vegetables in boiling water, which as previously explained, results in a significant loss of certain nutrients. By using this method, the vegetables do not make contact with the boiling water but are cooked by steam. Unlike boiling, this method better retains their texture and soften less.
The study found that steaming was by far the best way to cook broccoli as it not only preserved glucosinolates but significantly increased their initial concentration by 30%.
Steamed broccoli also had a positive impact on total carotenoid levels with an increase of 19% compared to raw ones.
Steaming broccoli it seems is the perfect formula until you see that 32% of vitamin C (ascorbic acid) was lost using this cooking method which is noteworthy for anyone looking to increase their vitamin C levels.
Frying
Frying involves cooking the vegetables in extremely hot oil which has an adverse effect on their nutritional value.
Frying led to the biggest reduction in total carotenoids in all 3 vegetables with a loss of total carotenoids in carrots of 14%, 35% in courgettes and 33% in broccoli.
Glucosinolate levels in broccoli showed substantial degradation when fried with huge loss of 84%.
Even though the ascorbic acid concentration in broccoli significantly decreased after all cooking treatments, it was especially evident again after frying, where a loss of 87% was detected.
It gets worse when you look at the vitamin C concentration in carrots after being fried where the levels could not even be detected.
So What Is the Best Way to Cook Vegetables?
When I set out to do my research on the subject of the best way to cook your vegetables, I stupidly thought that I would walk away with some clear actionable processes that would help you guys get the most nutritional benefit when you Cook your vegetables.
I couldn’t have been more wrong and have walked away with more knowledge plus a ton of confusion sprinkled in between.
Just like everything else nutritionally based there are no absolutes.
One cooking method may benefit a certain vegetable but be detrimental to another and visa versa.
But that still doesn’t paint the whole picture.
If we take for example the courgette, the total concentration of carotenoids was reduced when steamed but the value of one of the compounds ( β-carotene ) that make up part of the total value had increased. If you were looking to increase your intake of this antioxidant that converts to vitamin A, you could be fooled into thinking when looking at the reduction in the total concentration, that steaming was reducing its bioavailability when it is in fact the opposite.
What Have We Learned?
Here at quickness fitness we are all about keeping it simple and knowing the effect of every cooking method on every vegetable you eat makes no sense in the real world. As long as your consuming a mix of vegetables on a regular basis I wouldn’t worry too much about the science.
The most nutritious way to cook your vegetables it seems is actually the way that makes you eat them.
For me it was when I started to use a steamer that my vegetable intake sky rocketed. I always boiled my vegetables but never enjoyed the soft, soggy texture. For that reason I rarely cooked them and when I did couldn’t appreciate them. Now I eat vegetables almost daily with every meal and I really enjoy them.
