Eating nutritious foods can help improve your health and boost your energy levels. However, you may not be aware that the way you cook your food affects the amount of nutrients it contains.

Cooking food improves digestion and increases the absorption of many nutrients. Some nutrients actually become more readily available to the body when food is cooked.

But cooking can reduce several key nutrients, including:

  • water-soluble vitamins: vitamin C and the B vitamins — thiamine (B1), riboflavin (B2), niacin (B3), pantothenic acid (B5), pyridoxine (B6), folic acid (B9), and cobalamin (B12)
  • fat-soluble vitamins: vitamins A, D, E, and K
  • minerals: primarily potassium, magnesium, sodium, and calcium

However, the cooking method you choose can help prevent nutrient loss.

Boiling, simmering, and poaching are similar methods of water-based cooking.

These techniques differ by water temperature:

  • poaching: less than 180°F (82°C)
  • simmering: 185–200°F (85–93°C)
  • boiling: 212°F (100°C)

Vegetables are generally a great source of vitamin C, but a large amount is lost when they’re cooked in water. If you boil vegetables such as carrots, keep the skin on before cutting them up to prevent nutrients from escaping into the water.

B vitamins show a similar story. As they are also water-soluble, B vitamins may be lost when meat is simmered and its juices run off. To avoid this, you could either try another cooking method or collect and consume the juices that run off during the cooking process.

Some nutrients, however, may fare better with water-based cooking. For example, boiling fish was shown to preserve omega-3 fatty acid content significantly more than frying or microwaving.

Grilling and broiling are similar methods of cooking with dry heat. When grilling, the heat source comes from below, but when broiling, it comes from above.

Grilling is one of the most popular cooking methods because of the flavor it gives food.

However, minerals and B vitamins may be lost when the juices drip from the meat.

There are also concerns about polycyclic aromatic hydrocarbons (PAHs), which are potentially cancer-causing substances that form when meat is grilled, and fat drips onto a hot surface.

However, researchers have found that PAHs can be decreased by 41–89% if drippings are removed and smoke is minimized.

Microwaving is an easy, convenient, and safe method of cooking. Short cooking times and reduced exposure to heat help preserve the nutrients in microwaved food.

Less vitamin C is lost from green vegetables during microwaving than in most cooking methods.

It’s also possible to steam food in the microwave, which can be a great alternative to boiling or frying vegetables in order to retain as many nutrients as possible.

Steaming is one of the best cooking methods for preserving nutrients, including water-soluble vitamins, which are sensitive to heat and water.

Even microwave steaming may show these benefits. For example, steamed broccoli retains more of its beneficial glucosinolate compared with boiled or fried broccoli.

Steaming kale is the healthiest way to eat it, as it alters some enzymes, allowing your body to obtain the iodine from the vegetable.

If you find steamed vegetables taste bland, try adding some seasoning and oil or butter after cooking.

Roasting and baking involve cooking food in an oven with dry heat.

Although these terms are somewhat interchangeable, “roasting” is typically used for meat, while “baking” is used for bread, muffins, cake, and similar foods.

Most vitamin losses are minimal with this cooking method, including vitamin C.

However, due to long cooking times at high temperatures, the B vitamins in roasted meat may decline by as much as 40%.

With sautéing and stir-frying, food is cooked in a saucepan over medium to high heat in a small amount of oil or butter. These techniques are very similar, but with stir-frying, the food is stirred frequently, the temperature is higher, and the cooking time is shorter compared to sautéing.

In general, sautéing and stir-frying are healthy methods for preparing food.

Cooking for a short time without water helps prevent the loss of B vitamins, and the addition of fat may enhance the absorption of plant compounds and antioxidants.

On the other hand, stir-frying has been shown to significantly reduce the amount of vitamin C in broccoli and red cabbage.

Frying involves cooking food in fat — usually oil — at a high temperature. The food is often coated with batter or bread crumbs.

It’s a popular way of preparing food because the skin or coating maintains a seal, which ensures that the inside remains moist and cooks evenly. The fat used for frying also enhances the flavor of the food.

However, some nutrients can be lost if they are fat-soluble. For example, carotenoids in kale or carrots can be lost during the frying process.

Omega-3 fatty acids are also very delicate and prone to damage at high temperatures. Therefore, baking fatty fish may be better at preserving the omega-3 fatty acids compared with frying.

Another factor to consider is that oil heated to a high temperature for a long period of time forms toxic substances called aldehydes, which may increase the risk of cancer and other diseases. The type of oil, temperature, and length of cooking time affect the amount of aldehydes produced. Reheating oil also increases aldehyde formation.

When frying food, opt for one of the healthiest oils for frying.

Here are 10 tips to reduce nutrient loss while cooking:

  1. Use as little water as possible when poaching or boiling.
  2. Consume the liquid left in the pan after cooking vegetables.
  3. Add back juices from meat that drip into the pan.
  4. If you’re peeling your vegetables, wait until after you cook them to do so.
  5. Cook vegetables in smaller amounts of water to reduce the loss of vitamin C and B vitamins.
  6. Try to eat any cooked vegetables within a day or two, as their vitamin C content may continue to decline when the cooked food is exposed to air.
  7. Cut food after — rather than before — cooking, if possible. When food is cooked whole, less of it is exposed to heat and water.
  8. Cook vegetables for only a few minutes whenever possible, and avoid overcooking them.
  9. When cooking meat, poultry, and fish, use the shortest cooking time needed for safe consumption.
  10. Don’t use baking soda when cooking vegetables. Although it helps maintain color, vitamin C will be lost in the alkaline environment produced by baking soda.

It’s important to select the right cooking method to maximize the nutritional quality of your meal. However, there is no perfect cooking method that retains all nutrients.

In general, cooking for shorter periods at lower temperatures with minimal water gives the best results.