Steaming vs. Boiling: Which Cooking Method Preserves The Most Nutrients?

Vegetables are certainly one of the healthiest foods rich in vitamins, minerals, fiber, and protective plant compounds, they play a big role in maintaining general health and preventing common diseases. However, when it comes to cooking vegetables, how you cook them can make a difference in their nutritional value.

Among the most common cooking methods are boiling and steaming, both of which affect vegetables in different ways. Although boiling immerses the vegetables in water, steaming uses hot vapor to cook the food. So, should you steam or boil vegetables for the best health benefits?

Vegetables have such essential nutrients that they present loads of health benefits to humanity. They are not just rich in vitamins but carry beta-carotene also, which acts like a shield against oxidative stress from any source and decreases the chances of severe diseases like heart disease, cancer, and diabetes. In addition, vegetables act like a great source of dietary fibers, which are imperative to digest food, maintain healthy blood sugar, and increase satiety for a long time.

However, as healthy as vegetables are, the way they are cooked plays a huge role in how well our body can absorb these nutrients. The cooking method you choose can either enhance or diminish the nutritional value of your vegetables.

Steaming is considered to be one of the healthiest methods for cooking vegetables. In this method, the vegetables are placed in a perforated basket above boiling or simmering water and allow steam to rise and cook the food gently. Since steaming doesn't require direct contact with water, there is a loss of fewer nutrients as compared to boiling.

One of the main benefits of steaming is that it does help retain water-soluble vitamins, vitamin C and B vitamins, which are commonly leached out when boiled vegetables soak in water. Research evidence has shown that steaming can have a higher concentration of retention of some vitamins, including vitamin C, beta-carotene, and flavonoid antioxidants, than boiling does. In fact, it was found in a 2009 study that steaming broccoli, one of the healthiest vegetables, would retain the most nutrients in comparison to five other ways of cooking, including boiling, microwaving, and stir-frying.

Steaming also maintains plant compounds like flavonoids, which are among the most potent antioxidants known for their association with several benefits, including cancer prevention. A study on different cooking methods showed that steaming enhanced the flavonoid antioxidants in most vegetables, including broccoli, spinach, and carrots. However, some vegetables, such as carrots, are increased in beta-carotene when steamed. Beta-carotene is a form of vitamin A that is crucial for eye health and immune function.

One of the interesting results of comparative research between steaming and boiling is that the vitamin C loss is less during steaming, especially as it is one of the sensitive vitamins to heat and water. It has been demonstrated that, in terms of loss, steaming vegetables have shown a very minor loss of vitamin C, only 14%, after five minutes of steaming. However, a loss of 54% was noted when boiling the vegetables.

Boiling the vegetables can save so much time, but boiling the vegetables does not guarantee their highest nutrient retention. Boiling simply puts the vegetables under hot water and cooks it under direct heat. However boiling can be said to be very swift since it will result in getting rid of nutrients found in water. To explain, many vegetables have massive portions of vitamins; for example, vitamin C can be dissolved by hot water during boiling. Most, therefore will leach away from the prepared meals.

Aside from Vitamin C, beta-carotene is one of the few major losers in boiled foods. Laboratory tests done on peas and cauliflower reveal that their more than 50 percent levels of antioxidants were destroyed. Boiling also causes huge losses of vitamins and minerals to vegetables such as spinach, broccoli, and Brussels sprouts. If you have to boil your vegetables, try to limit the time and avoid overcooking to minimize the loss of nutrients.

Interestingly, some vegetables, like carrots, may benefit from boiling, as boiling has been shown to increase the bioavailability of beta-carotene. However, this benefit is typically outweighed by the significant loss of other nutrients when boiled.

If you’re looking for an alternative cooking method that preserves nutrients, microwaving could be a good option. Microwaving is the method of cooking food using electromagnetic waves and requires very less or no water. Thus, microwaving is a gentler method of cooking that helps retain water-soluble vitamins such as vitamin C. A study conducted in 2003 showed that vegetables such as zucchini, carrots, and beans, when cooked with little water in a microwave oven, had a significantly high amount of phytonutrients compared to those cooked by other methods, including boiling.

While steaming and microwaving are excellent ways for cooking vegetables, you can take it to the next level for maximizing the health benefits of your vegetables by using healthy fats in cooking. For instance, sautéing vegetables in extra-virgin olive oil can enhance the absorption of fat-soluble vitamins such as vitamin A, D, E, and K. Olive oil is also rich in antioxidants and polyphenols, which provide additional health benefits.

When cooking vegetables, do not overuse salt. Instead, season with fresh herbs, spices, and lemon juice. This will provide flavor without the negative health effects of too much sodium.

This argument in the war between steaming and boiling vegetables: it is simply a way to better retain the nutrients in food. This way of cooking helps in keeping vitamins and antioxidants from vitamin C, beta-carotene, and flavonoids that play an important role in human health.

The better it would be to steam the vegetables if you want to derive maximum health benefits from it. Steam or broccoli, spinach, carrots-any food cooked- is only allowed by steaming so that a maximum amount of nutrient value is retained. Further alternative, to microwaving, minimal water can be used too. No matter how one cooks his vegetables, add healthy fats like olive oil and season with herbs; in this way, nutrition of these vegetables will be maximized further.

Making small differences in how you prepare vegetables can make a big difference in your health. The next time you get ready to prepare a meal, steam it instead of boiling so that you have a much healthier, more nutrient-rich plate of vegetables.

Influence of cooking methods on antioxidant activity of vegetables. J Food Sci. 2009