Guest Feature: The Impact of Different Cooking Techniques on Nutritional Value

Guest Feature: The Impact of Different Cooking Techniques on Nutritional Value - Chefs For Foodies

Today's blog is a guest post by Melissa Kuman, better known as @thedeliciousnutritionist. Kuman has spent years studying nutrition, life coaching and neural-linguistic programming, and believes that the best way to achieve better health is not through forcing people into cookie-cut preconceptions of weight loss and dieting, but instead by creating healthy habits and tailoring a journey that best fits you.

One of the biggest nutrition misconceptions is that cooking decreases the nutritional value of food, and while it does alter them, this is not necessarily true. Cooking some foods can improve digestion and absorption of vitamins and minerals. So, lets discuss some of the most common cooking methods and how they affect the foods we eat.

Here are the 6 most common cooking methods and their impact on nutritional value:

  1. Grilling

A technique where food is cooked over a high heat source with smoke, flames, or charcoal; grilling gives food a deeper and richer flavour due to the moderate temperatures it requires.

Grilling can be considered a healthy way of cooking as it does not need a high amount of fat, such as butter or oil. There is no evidence that grilling impacts any nutrients, though there is some concern over the loss of Vitamin-B in the meat juices when cooking meat. However, grilling vegetables helps release nutrients from the cell wall, provides more bioavailability to the body. Examples of nutrients released include lycopene found in red peppers and beta carotene found in carrots.

At The Delicious Nutritionist, my favourite vegetable to grill is the sweet red pepper and asparagus – both full of antioxidant compounds and so tasty!

  1. Boiling

Boiling is one of the oldest cooking methods, it involves submerging food in a large body of liquid like stock or water at its boiling point.

Boiling has many advantages and disadvantages. One advantage is that it preserves amounts of the essential omega-3 in foods, which helps to lower the risk of heart disease, depression, and arthritis.

However, boiling can cause water soluble vitamins (namely vitamin C) to leach out of foods, decreasing the vitamin content. For example, boiling potatoes causes a small loss of vitamin C and B6, but does retain all the vegetable's fibre and potassium content! Potassium is a mineral that helps our nerves to function and muscles to contract and can be found in foods such as peas, cooked spinach, and cooked broccoli.

  1. Frying

Not to be mistaken for deep frying, pan frying preserves the nutrient and fibre content in some foods such as potatoes, and can even reduce aldehyde content when compared to deep frying. Toxic aldehydes occur when fatty acids are degraded in the deep frying process. Some are volatile and remain in the food after frying.

Stir-frying is an ideal way of cooking, since it requires low amounts of fat/oil. Coconut oil and sesame oils are the most popular oil to use in stir frying due to their high smoke point and great flavour. Cooking without water also prevents the loss of B vitamins, which aid the conversion of food into energy. Why not stir fry some mixed chopped vegetables, add tofu for your protein source and some noodles for a delicious, well balanced meal! For more ideas check out my Instagram page @thedeliciousnutritionist

  1. Steaming

Steaming is an excellent way to cook vegetables, as it preserves all nutrient content, including water soluble vitamins and enhances others like iron. Did you know the iron in spinach is more readily absorbed when the spinach is cooked? Steaming also makes fibre digestible, so you can absorb the nutrients more easily.

Although steaming is often associated with bland cooking, there are multiple ways to increase appeal, including adding spices and garlic. Steaming spinach and stirring in some garlic olive oil makes a tasty side dish to your meal!

  1. Microwaving:

Microwaving is one of the easiest and most time-effective ways of cooking. Microwaving also keeps ingredients in their natural state, retaining the nutrients while avoiding exposure to heat. Studies have found that microwaving is a safe and effective method for preserving nutrients, although there is a loss of vitamin C (up to 30%) in some foods, this is still lower than most other methods. Microwaving gives the same effect to steaming vegetables when you include a small amount of water, and it's also a lot quicker and easier.

  1. Roasting

Roasting is commonly utilised to bring out the flavours in foods.  Roasting presents minimal vitamin loss and is often recommended for a ‘healthier’ alternative if cooked with low amounts of fat. It is a great way to batch cook vegetables to make into salads and soups.


The type of cooking method used when making a meal is one of the most important factors to consider, as there are many different cooking methods, each with their own set of advantages and disadvantages. While there is no single best cooking method, there are some things to keep in mind when selecting the right cooking method, such as desired taste and texture. Cooking for shorter periods at lower temperatures with minimal water will produce the best results in terms of preserving nutrients.

Comment below your favourite method of cooking food!

If you liked these cooking tips, check out Melissa's YouTube videos here or visit her website here, where you can learn about health and nutrition