The main rule of thumb for healthy cooking is to avoid methods that require excessive fat. For that reason, I urge you not to fry food and especially to avoid deep-frying. In addition to extra calories, frying exposes you to the health risks of oxidized fats, which promote inflammation and cancer.
Here’s a rundown of the cooking methods I consider healthy:
- Stir-frying: This lets you cook foods quickly over high heat, combining vegetables and protein in a lightly oiled wok or frying pan. Use small amounts of good oils (described below) and keep them below the smoking point.
- Steam frying: Here you sauté food briefly in a little oil, then add water, stock or wine and cover the pan. When the food is almost done, uncover and boil off any excess liquid.
- Broiling, baking and roasting can also be healthy methods of preparation, provided you don’t add unnecessary fat.
- Steaming: This is a particularly healthy cooking technique because it does the least damage to nutrients and, as a bonus, lends itself to a quick cleanup. I often steam vegetables and fish and tend to steam tender vegetables (such as broccoli and asparagus) and boil less delicate ones (potatoes, beets, corn on the cob). I like my vegetables when they have a deep color to them and are a bit crunchy.
- Grilling: I enjoy grilling outdoors, but high temperature grilling (and broiling) of foods that contain fat and protein (meat and poultry, especially) produces carcinogenic compounds called heterocyclic amines (HAs) that can raise the risk of colorectal cancer in those with a genetic predisposition to the disease and may increase the risk of other cancers. To avoid HAs grill more vegetables and fish and less meat and try not to cook animal foods (including fish) to the point of charring. (Blackened fish is unhealthy – try to avoid the blackened parts if you’re served food this way.) If you do grill meats, use leaner cuts and marinate meat, poultry and fish before cooking. The marinade may help reduce HA formation, especially if it includes ginger, rosemary or turmeric. And, finally, avoid charcoal lighter fluid or self-starting packages of briquettes in a charcoal grill – they will leave residues of toxic chemicals in your food. A healthy alternative is an inexpensive chimney lighter that uses a small amount of newspaper to ignite a mass of charcoal in a large metal cylinder. Gas grills are good alternatives to those that use charcoal.
Here are the oils I recommend for healthy cooking:
- Olive oil: With the highest percentage of heart-healthy monounsaturated fat of any edible oil quality olive oil also contains abundant antioxidants, substances that have been shown to provide cardiovascular and anti-cancer effects. Use olive oil for all cooking except when you want a more neutral taste.
- Canola oil: Primarily a monounsaturated fat and, as such, healthier than saturated fats or polyunsaturated oils. However, I consider canola oil a distant runner-up to olive oil. I use canola oil in moderation, when I want a neutral-tasting oil.
- Grapeseed oil: This is another option when you want a neutral flavor. You can use it for sautéing. Grapeseed oil has the advantage of a higher smoke point than canola oil. Buy only organic expeller-pressed grapeseed oil and once a bottle is opened, keep it in the refrigerator.
- Algae oil: This healthy oil has an excellent fatty acid profile and more monounsaturated fat than olive oil. I’ve been using algae oil at home for sautéing when I don’t want the flavor of olive oil.
Andrew Weil, M.D.