You are choosing healthy foods, but you are going to miss those vital nutrients if cooking destroys them. To meet your body’s requirements correctly, you also need to know the right way of cooking. Losses to various nutrients like water-soluble vitamin A, B, C, vital fats & oils, and as well as some minerals. Some cooking methods also make proteins dry and rubbery and thus make them hard to digest. (1) And some methods generate carcinogenic compounds. You need to know what cooking methods you can use to what foods. This article will help you to understand the inside facts and as well as to choose the healthiest cooking methods to retain nutrients in foods.
Healthiest cooking methods to retain nutrients in foods
In general high temperature, pressure, and longer duration of cooking cause more loss of nutrients. When you use water in cooking your veggies, water-soluble vitamins leach out. Knowing the fundamental facts, you can make your cooking healthier as well as prevent the generation of carcinogens.
Steaming is one best method of cooking to prevent loss of nutrients, antioxidants as well as other phenolic compounds like chlorophyll, glucosinolates, etc. (2,3) Vitamin C is one of the most easily lost vitamins from foods. In a study, researchers found a minimal loss of vitamin C as 8.6-14.3% in broccoli, spinach, and lettuce with steaming. (4)
However Steamed foods lack taste. You can use short-duration light stir fry with low temperature after steaming to enhance the taste.
As the name, this method uses the microwave to cook foods. Surprisingly micro oven cooking doesn’t cause excessive loss of vital nutrients such as vitamin C, antioxidants. For example, mushrooms showed the high retention of phenolic compounds i.e. antioxidant activity during microwaving compared to other forms of cooking. (5) In testing of antioxidant activity in cooking methods boiling, microwaving, pressure-cooking, griddling, frying, and baking, researchers found griddling, microwave cooking, and baking had produced the lowest losses, while pressure-cooking and boiling lead to the greatest losses; frying occupies an intermediate position. (6) Loss of omega 3 also observed as a minimum in microwave cooking. (7) While a large amount of water can lead to nutrients loss, adding a small amount of water essentially steams food from the inside out. That helps to cook at a faster rate as well as retain more vitamins and minerals. (8) And you need to choose microwave-friendly cookware.
Broiling and grilling
These cooking methods have some problems with cooking meat as that can cause the formation of cancer-causing compounds polycyclic aromatic hydrocarbons (PAHs) and heterocyclic amines (HCAs). PAHs form when fat from the meat drips onto the fire or grill element. Polycyclic aromatic hydrocarbons (PAHs) can rise up and seep into the meat. (9) And on the other hand, when you use high-heat cooking HCAs can form.
Another concern with both grilling and broiling includes as these types of cooking promote the formation of harmful advanced glycation end products (AGEs).
If you are taking grilled meat it is a good idea to have anti-oxidant rich vegetables and fruits at the same time. Marinating is another good idea. Marinating food than before grilling has shown to reduce the formation of HCAs in some research. Also, frequent flipping food may help to reduce the formation of HCAs. (10) Overall it is not a very good way of cooking meat.
Deep frying increases the temperature of cooking to a very high extent. Although deep frying may enhance flavor and crispiness, this cooking method generates high level several toxic and cancer-causing compounds like by-products like AGEs, aldehydes and HCAs. (11,12,13,14)
Stir-frying occupies an intermediate position and retains a decent amount of nutrients. This method doesn’t cause too much nutrients loss. However, if you high heat for a longer time you are going to lose more nutrients. This type of cooking can cause a considerable amount of loss of vitamin C in vegetables. One study reported 21.2-28.1% loss of vitamin C with cruciferous vegetables like broccoli, spinach, and lettuce with stir-frying. (15) You should avoid high-temperature cooking or dry pan-frying of foods more specifically meat, poultry as well as fish to prevent the formation of cancer-causing compounds. (16, 17) Alternatively, you can also use a little amount of water or moisture as a safer cooking option.
Some cruciferous vegetables contain a higher amount of goitrogenic compounds that interfere with iodine uptake and finally impair thyroid function. You may read about how to reduce goitrogenic compounds from cruciferous vegetables.
When you boil food in water, water-soluble vitamins will leach out. In testing with mushroom, boiling significantly decreased the total phenolic contents i.e. reduced antioxidant activity of mushroom. (18) Another study also observed a significant decrease in antioxidant with boiling. (19) Researchers found 40.4-54.6% of loss of vitamin C in broccoli, spinach, and lettuce with boiling. (15) However, consuming broth you can still have a considerable portion of those nutrients. (20)
On the other hand, the boiling of fish showed higher retention of omega 3 fatty acids than frying or microwaving. (21)
While some thought both combinations of pressure and temperature of pressure cooker cooking destroy nutrients, the findings go to some other ways. Pressure cooking also reduces cooking time as an advantage and forces moisture to enter into foods. A study on spinach and amaranth leaves recommended the storage of leaves in refrigerator, drying in an oven, blanching for shorter time and cooking in a pressure cooker for better retention of these two vitamins. (22) In another study published in the Journal of Food Science found pressure cooking had good retention of vitamin C in broccoli and also caused less loss of potential cancer-fighting compound sulforaphane of cruciferous vegetables in broccoli. (23) In a study in Korea, pressure cooking had reduced carcinogenic aflatoxins to a higher degree(78−88%). (24)
Although there is some degree of nutrients loss, pressure cooking is not such a bad type of cooking as appeared. Foods that expand too much like cereals, oats can block the steam vent. Therefore you should avoid such foods in pressure cooking.
Although fermentation is not a conventional method of cooking, fermented foods with probiotics and prebiotics promote gut health along with other benefits. We know why gut health is very important to our overall health. But you need to know the right way, how to ferment foods and what foods to be fermented.
Like many other things, no cooking methods are perfect. Just remember in general high temperature, pressure and longer cooking duration cause more nutrients loss. Cooking meat poultry or fish with direct heat or dry cooking may generate carcinogenic compounds. Nutrients losses also occur with various processes like the peeling of fruits and vegetables, discarding of edible leaves of vegetables like carrot, cabbage, cauliflower, dehydration as well as prolong storage. Cutting of foods into small pieces reduces cooking time but also increases surface area. You need to cook vegetables immediately after cutting into pieces. Overall having the idea, you can prevent excessive nutrients loss in cooking as well as the formation of carcinogens.
Disclaimer: Information provided here are generalized information for educational purpose only, not intended to provide one to one health consultation or replace practice of a qualified practitioner. Different people may have different health condition and may have different reaction to the same food. Hence it has been advised to consult with health care provider before application of any of above information Source and references: 1.http://agritech.tnau.ac.in/nutrition/nutri_cookingtips_nutrient loss.html 2. Yuan GF, Sun B, Yuan J, Wang QM.,Effects of different cooking methods on health-promoting compounds of broccoli,J Zhejiang Univ Sci B. 2009 Aug;10(8):580-8 3.Xu F, Zheng Y, Yang Z, Cao S, Shao X, Wang H.,Domestic cooking methods affect the nutritional quality of red cabbage, Food Chem. 2014 Oct 15;161:162-7 4.Zeng, C. (2013), "Effects of different cooking methods on the vitamin C content of selected vegetables", Nutrition & Food Science, Vol. 43 No. 5, pp. 438-443. https://doi.org/10.1108/NFS- 11-2012-0123 5.Liping Sun, Xue Bai, and Yongliang Zhuang, Effect of different cooking methods on total phenolic contents and antioxidant activities of four Boletus mushrooms, J Food Sci Technol. 2014 Nov; 51(11): 3362–3368. 6. Jiménez-Monreal AM, García-Diz L, Martínez-Tomé M, Mariscal M, Murcia MA.,Influence of cooking methods on antioxidant activity of vegetables,J Food Sci. 2009 Apr;74(3):H97-H103. doi: 10.1111/j.1750-3841.2009.01091.x. 7. Nimish Mol Stephen, R. Jeya Shakila, G. Jeyasekaran, and D. Sukumar,Effect of different types of heat processing on chemical changes in tuna,J Food Sci Technol. 2010 Mar; 47(2): 174–181. 8.https://www.health.harvard.edu/staying-healthy/microwave- cooking-and-nutrition 9.Lee JG, Kim SY, Moon JS, Kim SH, Kang DH, Yoon HJ., Effects of grilling procedures on levels of polycyclic aromatic hydrocarbons in grilled meats,Food Chem. 2016 May 15;199:632-8. doi: 10.1016/j. 10.https://www.webmd.com/food-recipes/features/a-healthier-way- of-grilling#1 11.Peng CY, Lan CH, Lin PC, Kuo YC.,Effects of cooking method, cooking oil,and food type on aldehyde emissions in cooking oil fumes, J Hazard Mater.2017 Feb 15;324(Pt B):160-167 12.Chen G, Smith JS.,Determination of advanced glycation endproducts in cooked meat products, Food Chem. 2015 Feb 1;168:190-5 13.Omojola AB, Ahmed SA, Attoh-Kotoku V, Wogar GS.,Effect of cooking methods on cholesterol, mineral composition and formation of total heterocyclic aromatic amines in Muscovy drake meat,J Sci Food Agric. 2015 Jan;95(1):98-102 14. S J, Iqbal SZ, Talib NH, Hasnol ND.,Heterocyclic aromatic amines in deep fried lamb meat: The influence of spices marination and sensory quality, J Food Sci Technol. 2016 Mar;53(3):1411-7 15.Zeng, C. (2013),"Effects of different cooking methods on the vitamin C content of selected vegetables", Nutrition & Food Science, Vol. 43 No. 5, pp. 438-443. https://doi.org/10.1108/NFS- 11-2012-0123 16.Gibis M, Kruwinnus M, Weiss J., Impact of different pan-frying conditions on the formation of heterocyclic aromatic amines and sensory quality in fried bacon, Food Chem. 2015 Feb 1;168:383-9. 17.Liao GZ, Wang GY, Xu XL, Zhou GH., Effect of cooking methods on the formation of heterocyclic aromatic amines in chicken and duck breast,Meat Sci. 2010 May;85(1):149-54 18.Liping Sun, Xue Bai, and Yongliang Zhuang, Effect of different cooking methods on total phenolic contents and antioxidant activities of four Boletus mushrooms, J Food Sci Technol. 2014 Nov; 51(11): 3362–3368. 19.Murador D, Braga AR, Da Cunha D, De Rosso V., Alterations in phenolic compound levels and antioxidant activity in response to cooking technique effects: A meta-analytic investigation,Crit Rev Food Sci Nutr. 2018 Jan 22;58(2):169-177 20.https://goaskalice.columbia.edu/answered-questions/cooking- veggies-and-vitamin-loss 21.Nimish Mol Stephen, R. Jeya Shakila, G. Jeyasekaran, and D. Sukumar,Effect of different types of heat processing on chemical changes in tuna,J Food Sci Technol. 2010 Mar; 47(2): 174–181. 22. Yadav SK, Sehgal S.,Effect of home processing on ascorbic acid and beta-carotene content of spinach (Spinacia oleracia) and amaranth (Amaranthus tricolor) leaves,Plant Foods Hum Nutr. 1995 Feb;47(2):125-31. 23.F. Galgano, F. Favati, M. Caruso, A. Pietrafesa, S. Natella,The Influence of Processing and Preservation on the Retention of Health‐Promoting Compounds in Broccoli,Journal of Food Science, Volume72, Issue2 March 2007,Pages S130-S135 24.Je Won Park, Young-Bae Kim,Effect of Pressure Cooking on Aflatoxin B1 in Rice, J. Agric. Food Chem. 2006, 54, 6, 2431-2435