Ever hear the phrase “Food is medicine”? Though this common aphorism is a generalized blanket statement, it is true that a balanced diet can serve as a foundational basis to support the human body to function at its full potential. Yet, the exact mechanics of how to preserve peak nutritional value in our food can be confusing and daunting with the myriad never-ending to-dos on our mental lists taking up most of the space. Healthline lets this thought process cook in their article “How Cooking Affects the Nutrient Content of Foods,” examining popularized cooking methods for how much nutritional value remains in the finished product.

How food is prepared has a larger impact on the nutritional value passed on, and we aren’t just talking about when a chef decides to drown your dish in butter. Certain nutrients are often lost in varying degrees during cooking time, such as water-soluble vitamins, fat-soluble vitamins and minerals. A few key vitamin and mineral groups in these categories include vitamin C, B, A, D, E, K, as well as potassium, magnesium, sodium and calcium. Cooking does provide needed improvements in digestion and absorption of many nutrients, but being aware of what may be lost in the process is instructive.

Nutrient Retention Tips

Here are some helpful ways to get the most nutrition out of your food when cooking:

  1. When poaching or boiling, limit water use to what is necessary.
  2. If possible, remember to consume the liquid left in the pan after cooking vegetables. Perhaps it can be incorporated into a sauce.
  3. For flavor and added nutrition, reincorporate juices from meat that drip in the pan.
  4. It doesn’t appeal to peel your vegetables. Unpeeled veggies retain more fiber and nutrient density.
  5. Smaller amounts of water in cooking reduces loss of vitamins C and B.
  6. Plan 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. If possible, cook food whole so that less of the item is exposed to heat and water. This will sometimes extend cooking times, however, so it may defeat the purpose if the food product is particularly large. Cut food as desired after cooking, if possible.
  8. When it makes sense to do so, cook vegetables for only a few minutes whenever possible.
  9. When safe do so, consider using shorter cooking times for meat, poultry and fish. Invest in a meat thermometer to make sure your food has reached safe temperatures.
  10. Some cooks add baking soda to vegetables to help maintain color, but it isn’t recommended because vitamin C will be lost to the alkaline environment created.

Overall, there isn’t a perfect universal cooking method that retains peak nutrients, but being thoughtful about your approach can make a big difference.

Cooking with Water

Water-based cooking is the cooking type with the most loss of water-soluble vitamins. Water-based cooking means that a food item is poached, simmered or boiled. Generally, the difference relates to the temperature used, less than 180°F to poach, 185-200°F to simmer and 212°F to boil.

Vegetables often serve as an excellent vitamin C source, but a significant portion of the nutrient is lost to cooking. When boiled, broccoli, spinach and lettuce can lose roughly half their vitamin C content, as the nutrient is water-soluble and heat sensitive, leaching out of veggies when immersed in hot water. Meat can also lose nutritional content when simmered, as B vitamins are sensitive. Up to 60% of thiamine, niacin and other B vitamins may cook out into the juices that run out of the meat. However, if the liquid of the meat is consumed, all of the minerals and 90% of B vitamins are still present. In regard to fish, boiling is encouraged compared to frying or microwaving, as it will better preserve vitally important omega-3 fatty acids.

To Grill or To Broil?

Grilling evokes memories of summer cookouts, campfires and sharp grill lines on a juicy steak or a scrumptious veggie kebab. Broiling is the lesser-known twin method, as grilling mostly means to cook on a grilled service from below while broiling uses a heat source above. Both have similar effects to food, with up to 40% of B vitamins and minerals potentially lost in nutrient-rich juice or droppings. If some of that content is collected, it may preserve some nutritional value.

However, if you are a certified grill master, remember to clean your grill often with safe cleaners. If lots of food and fat is left to char, it can create excess polycyclic aromatic hydrocarbons (PAH) that can become carcinogenic.

Surprising Facts About Your Microwave 

The humble microwave gets a bad rap, hogging counterspace and mostly being viewed as a quick way to warm up day-old pizza. Yet, its shortened cooking time and reduced heat exposure can have some benefits in nutrition preservation. More study is required to know the full potential impact of microwaving on nutritional values, but it is positive to see that microwaving green vegetables only loses about 20-30% of its max nutritional value, a significant improvement compared to other cooking methods.

Losing Value When Turning up the Heat 

As a general rule, the longer and the hotter you cook something, the more nutrition is lost. Let’s look at a few other popular cooking methods to see how they compare in this equation:

Roasting and Baking- This term refers to cooking with dry heat, often in an oven. They are somewhat interchangeable, but roasting usually refers to meat or vegetables, while baking refers to baked goods like bread, muffins or cakes. Loss of vitamins is minimal with this method, with the exception of B vitamins in roasted meat.

Sauté and Stir-Fry- These techniques require food to be cooked in a saucepan over medium heat in small amounts of oils or butter. Stir-frying is similar to sauté, but it requires higher temperature and shorter cooking time. Short cooking times with no water help prevent loss of B vitamins, and adding some fat can actually improve absorption of nutrients and antioxidants found in plants. Stir-frying can reduce vitamin C levels significantly in produce such as broccoli and red cabbage.

Frying- Traditional frying in oil is needless to say not the healthiest cooking method in general, but let’s see how it effects nutritional value for those that enjoy fried foods in moderation. Frying fish, especially fatty fish such as tuna, is not recommended due to significant loss of omega-3s. In this case, baking is a better bet.

However, frying can have some health benefits in certain situations, such as preservation of vitamin C and B vitamins, as well as increased fiber in potatoes. Care needs to be taken with frying because oil heated to a high temperature for long time periods can create toxic substances called aldehydes, which are linked to increased risk of developing cancer or other diseases. Oil type, temperature used and cooking time all play a role in how much aldehyde is produced. It can also be risky to reuse reheated oil, as it can lead to additional aldehyde forming. As a rule of thumb, try not to overcook your food if you decide to fry something and try to select a healthy cooking oil if possible, such as coconut oil or olive oil.

Steaming- Steamed vegetables retain their nutrients remarkably well, with minimal loss. Some people do find steamed vegetables bland, but seasoning, oil or butter can rectify that.

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