Over the last two columns (part 1, part 2) I have tried to make the point that we’d be a lot better off if we observed some natural limitations and stuck with the oils and fats we have been eating for most of our evolution. The problem we have with fat relates almost entirely to our use of oils that we have never traditionally eaten, either because we lacked the technology to extract them, or nobody ever considered them to be food. Many of the food oils used nowadays come from plants that have a very low fat content, such as grape seed (6% fat), corn (12% fat) and soy (20% fat), and thus require intensive extraction and refinement. Sometimes the reason to use an oil is based on little more than greed, as a way to make money from industrial by-products like cottonseed. Other times it is a novel invention, like using safflower or peanut oil, neither of which has significant historical evidence to back up their use as food oils.
Based on extensive research, the following is a list of the best fats and oils for daily consumption, and the upper limit for cooking temperatures:
• extra virgin coconut oil (not copra) (low-medium heat)
• organic palm and palm kernel oil (medium heat)
• extra virgin olive oil (low-medium heat)
• extra virgin sesame oil (low-medium heat)
• extra virgin almond oil (low-medium heat)
• organic butter (low-medium heat)
• extra virgin avocado oil (medium heat)
• organic (grass-fed) ghee (medium-high heat)
• organic lard, tallow and other home-rendered animal fats (medium-high heat)
Note that I have not included many of the cold-pressed vegetable oils commonly touted as being a valuable source of essential fatty acids, including canola, walnut, pumpkin, hemp, flax, sunflower, safflower or perilla oil. Nor do I include essential fatty acid supplements such as borage, evening primrose and black currant oil on this list. While many of them such as walnut, flax and hemp seed are rich in fat, none of them were ever used as food oils since shortly after pressing they rapidly begin to oxidize, causing adjacent fatty acids to link together and polymerize. This makes them effective ‘drying oils’ traditionally used in paints and varnishes to seal and preserve wood – but not as food. Apart from the damage that occurs to these oils during processing and storage, cooking these oils has also been shown to generate health-damaging lipid peroxides.
To lengthen shelf life and preserve the quality of cooking oils store them under cool, dry conditions. Even if a fat is naturally high in saturated fatty acids, factors such as humidity, heat, light and oxygen will all promote rancidity. Generally speaking, no fat or oil should be used for high-heat cooking.
Different types of fats have different properties, and traditional cultures have provided us with a detailed framework of what they are and how to use them. Generally speaking, fatty foods are reserved for people suffering from a vital deficiency, displaying signs such as weight loss, depressed immunity and weakness. Fatty foods are particularly useful for nourishing the brain during both gestation and childhood, to restore women after pregnancy, and in older people who show signs of wasting. In his excellent book on diabetes management, Dr. Richard Bernstein suggests that increasing the intake of fat upwards of 40% of the total caloric intake can be very helpful to stabilize blood sugars and insulin levels in diabetics. In Ayurveda, fatty foods are typically avoided in the obese, in people with weak digestion, or in the presence of excess mucus, congestion or a fever. Fatty foods are also avoided in active multiple sclerosis, a disease in which the immune system attacks the fatty tissues of the nervous system.
Among the fats described by Ayurveda ghee is perhaps the most celebrated. Prepared from cultured butter ghee has a sweet taste and is cool, heavy and wet in quality. It balances the nervous system and reduces inflammation, rejuvenates the body and enhances virility. Topically ghee is anti-inflammatory and finds special utility in diseases of the eye and skin, especially when prepared with bitter-tasting herbs such as barberry (Berberis spp.) and the Ayurvedic herbal formula Triphala. Like honey ghee is called yogavahi in Ayurveda, meaning that it contains the ability to augment the effects of any medicinal agent it is combined with. It is often combined with honey for its nutritive effects, but never in equal quantities. Although generally good for digestion, ghee can block the channels of the body and promote congestion if the body is toxic.
Sesame oil (taila, gingelly oil) is another highly recommended food oil, and is the primary medium for the many different types of medicated oils used in Ayurveda. Unrefined extra-virgin sesame oil has a sweet flavor, and is warm, heavy and wet in quality. It is used to balance the nervous system, enhance strength, nourish sexual function and clear the complexion. Applied topically sesame nourishes the skin and nervous system, helping to balance pain in the muscles and joints. Coconut oil is a common oil used in the south of India, with a sweet flavor and a cool, wet and heavy quality, making it suitable to balance both pitta and vata. It is applied to reduce heat and inflammation and nourish and protect the skin. Most coconut oil comes from roasting the dried fruit (copra), which damages the integrity of the oil. Look for extra virgin coconut is the prere either pressed from the dried fruit mechanically, or skimmed and purified from the fermented fruit. Olive oil and almond oil are both sweet in flavor, have a warm, heavy and wet quality, and are excellent to balance the nervous system and skin. Animal oils including lard and tallow are sweet in flavor and warm, heavy and wet in quality, and are useful for balancing the nervous system and treating dryness. When used topically as medicated oils and salves, animal fats are much better absorbed, and are better carriers for medicinal herbs than vegetable oils. Among the different oils marrowfat is the most nourishing, used in conditions such as wasting and immunodeficiency conditions.
Fish oils derived from fatty fish including herring, menhaden and ooligan (smelts) were exceptionally important foods utilized by many traditional peoples all over the world. They were typically produced by fermenting the freshly caught fish for up to two weeks, and then rendering off the oil by simmering at low heat in water. Rich in fat-soluble vitamins including vitamins A, D, E and K as well as omega 3 fatty acids, these rendered oils were not only an important dietary supplement, they were a valuable commodity for all coastal peoples, traded with in-land peoples for other goods such as animal pelts and dried meat. In North America these ‘grease trails’ were extensive trading routes that extended deep into the interior, well beyond the Rocky Mountains, from Alaska all the way south to northern California. Recent scientific interest in the health benefits of fish oils has spawned a relatively new industry, and these oils are now found in the marketplace as a ubiquitous health food supplement. To meet consumer demand however, this type of fish oil is a highly refined product, and has undergone extensive processing to remove the characteristically fishy taste of traditional fish oils, as well as impurities and biological toxins. While there is research suggesting a benefit in consuming omega 3 fatty acids, there is very little data on the effect that refinement has on the purported health benefits of the final product. Rich in polyunsaturated fatty acids including eicosapentaenoic (20:5) and docosahexaenoic (22:6) acid, fish oil appears to be even more unstable than vegetable oil, and undergoes rapid deterioration under even optimal storage conditions, giving rise to health-damaging constituents. Although there are clear benefits to eating oily fish, contradictory evidence raises questions about the safety of fish oil supplements if more than a month old from the date of manufacture.
