Cooking at Home: A Healthy Cooking Approach that Supports Nutritional Quality and Reduces Nutrient Loss in Vegetables

By Sandra A. Farrell, MPHN, BA

Home cooked meals can serve up a host of benefits such as improving diet quality, maintaining healthy eating habits, while reducing the risks of chronic diseases. Cooking at home offers numerous nutritional advantages, primarily due to the control it provides over ingredients such as salt, sugar and oil.

Vegetables are important components of our diet and methods of food preparation and cooking, can improve their nutritional quality and minimise nutrient loss.

As a Public Health Nutritionist and trained chef, while preparing meals at home, I make decisions about how to maximise nutrient content of plant foods and identify the critical phases during preparation and cooking, when the nutrients might be lost. Following are some tips on healthy cooking that I use.

Nutrient focused cooking

• During food preparation, whenever possible, I avoid cutting vegetables before cooking, preferring to cook them whole, as it helps to preserve nutrients, vitamins and minerals by reducing exposure to oxygen and heat.

• I use chopped fruits without delay, to protect their nutritional quality, texture, flavour and freshness.

• I use shorter cooking times when cooking, but ensuring that vegetables are properly and safely cooked, minimal water and gentle heat to help maximise nutrient retention.

• In addition to ingredient choice that meets our health needs, cooking methods can impact how many nutrients are provided. When cooking at home, try to avoid unhealthy cooking methods such as deep frying and long periods of high temperature cooking.

• Opt for healthier cooking methods such as steaming, stir frying, sautéing, microwaving, baking and roasting (at moderate temperatures) with minimal oil. I avoid overcooking and enjoy vegetables with a crunch, as they will retain more nutrients this way.

Maximise vitamin retention

• Instead of peeling vegetables, gently scrub them with a vegetable brush, as many nutrients and phytonutrients are concentrated just under the skin. When cooking, I leave vegetable skins on to retain nutrients.

• I often steam vegetables for a few minutes to reduce vitamin and mineral loss. Steaming retains texture, colour and doesn’t add calories, as you don’t need to use oil.

• Water soluble B and C vitamins, fat soluble vitamins A, D, E, K and minerals such as potassium and calcium are easily destroyed during preparation and cooking. This occurs when they are exposed to heat, light, water and oxygen.

• Boiling vegetables can result in vitamins leaching in the water. To minimise loses, avoid prolonged boiling, use minimal water, steam or stir fry instead and use leftover cooking water in soups, stews, sauces, gravies and curries.

An evidence based framework of healthy cooking suggests the following:

• Cooking Frequency: Decision to cook at home opposed to going to a restaurant or ordering a takeaway. Cook from scratch, prepare meals from basic ingredients and without the use of ultra-processed foods.

• Techniques and Methods: Avoid cooking meat with high temperature methods, avoid deep frying foods and use low fat cooking methodologies such as steaming, baking and grilling. Accurately measure ingredients such as salt, sugar and oil.

• Minimal Usage: Limit red meat, limit / avoid processed foods, limit animal fats.

• Additions/Replacements:  Add unprocessed fruits and vegetables to main dishes, use olive oil, replace refined grains with whole grains.

• Flavourings: Reduce salt, avoid margarine and cream based sauces on vegetables, use herbs, spices, citrus and alliums (onions, garlic and shallots).

Research studies conducted and cited in the International Journal of Gastronomy and Food Science suggest the following:

• Steaming seems to be the best method for maintaining the nutritional qualities (phytochemicals, carotenoids and folate).

• The best methods for cooking onions were sautéing and baking to improve flavonols’ content.

• Sous vide cooking which involves cooking in a vacuumed plastic pouch at precisely controlled temperatures was the best method for folate retention.

• Studies found that boiling whole potatoes (skin and flesh) did not result in significant reduction in folate content.

• Soaking and cooking legumes (peas, beans and lentils) were effective in removing or reducing anti-nutrients such as tannins and phytic acid (phytate).

• Soaking with salt, discarding water and cooking in fresh water was the best method to reduce cooking time and to improve the texture, protein quality and appearance of beans while reducing gastric issues.

About the Author

Sandra A. Farrell is a UK based Registered Nutritionist and member of Plant Based Health Professionals (UK). She has a MSc in Global Public Health Nutrition, BA (Hons) in Food, Nutrition and Professional Cookery and is a certified Health Coach. Sandra is presently pursing studies in Behavioural Science to promote health and wellbeing.

Disclaimer:

The contents of this article, regardless of date, is not intended to replace personalised medical advice from your doctor or healthcare professional.