Fats – Some History
Between 1950 and 1970, deaths across the U.S. from heart disease increased steadily (heart.org report). By 1970, there was a growing belief that consumption of fats was the main culprit; that prompted a government effort to persuade people to reduce or eliminate fat from their diets. Unfortunately, the blanket condemnation of all fats not only was unnecessary but probably damaging. At the time, the decision was contested by many researchers as being over-simplistic. It already was clear back then that refined carbohydrates were part of the problem too—or even most of the problem.
A particularly harmful result of the all-fats-are-bad approach was that fats in the diet rapidly became replaced by refined carbohydrates (sugar and white flour). The absence of fat in food made it feel less satisfying to many people, and that satisfaction deficit was filled with sugar and starch—exactly the opposite of what was needed.
Today, it’s clear that some fats are necessary in our diets and that lowering the level of those needed fats causes health problems. Some fats and oils in our food are good for us. These include omega-3, omega-6 and omega-9 groups of fats, and others, including butyrates. Dangerous fats are industrial trans-fats. Fats that lie somewhere in between are certain saturated fats, once thought to be dangerous. Now, the experts aren’t so sure: Some may be beneficial, some probably are not good.
Beneficial Fats
Fatty acids are critical for cell health and renewal throughout the body. These fats strengthen your cells and help them to hold moisture.
Omega group fatty acids are involved in supporting important body functions, including circulation, cell-building, skin renewal and brain functioning. They are critical for skin health and joint health, and they can fight heart disease, depression and Alzheimer’s.
Two omega fatty acids are defined as essential because they cannot be synthesized within the body: alpha-linolenic acid (ALA, an omega-3 fatty acid) and linoleic acid (LA, an omega-6 fatty acid). Another, oleic acid (an omega-9 fatty acid), can be synthesized within the body from omega-3 and omega-6 fatty acids but only in limited quantities, so the body also needs a food source of omega-9.
Other important omega-3 fatty acids are eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). EPA helps control inflammation throughout the body and may reduce symptoms of depression. DHA is important for brain development and maintenance. If we consume enough ALA from dietary sources, then the body can convert some of it to EPA and DHA. But if our intake of ALA is insufficient, we can’t make it ourselves.
We can obtain ALA and other omega-3 fatty acids from many vegetables, beans, nuts, seeds and fruits. Especially good sources are flax seeds, chia seeds, walnuts, kidney beans and black beans. Olive oil and oils made from flax seeds, canola seeds, sunflower seeds and soy beans all contain omega-3. Marine algae and phytoplankton are good omega-3 sources, which is why oily fresh fish (that eat algae and plankton) also are a valued source of the EPA and DHA omega-3 fatty acids (but not necessarily of ALA).
Most sources of omega-3 are also sources of omega-6. However, omega-6 can be obtained from other products, like cold-pressed olive oil, palm oil, whole grains, poultry and eggs. Because of the wider range of sources, humans generally ingest more omega-6 than omega-3 (and easily obtain sufficient omega-6 from a normal healthy diet). Ideally, intake of omega-3 and omega-6 should be in balance, but typical food choices today provide around 10 times as much omega-6 fatty acids as omega-3. That’s why it’s important to supplement omega-3.
Oleic acid, one of the most common fats in the body, plays a role in skin health and in managing cholesterol levels. Good sources of oleic acid and other omega-9 acids include: olives, nuts, seeds and oils cold-pressed from those foods. Olive oil is very high in oleic acid (and also is a good source of omega-3 and omega-6).
Butyrates are compounds formed from butyric acid (a fatty acid). They are essential for stomach health as they provide food for good bacteria, a strong population of which is vital for a healthy body. Some stomach microbes can consume dietary fiber and convert that fiber to butyrates—so dietary fiber is not just a source of bulk in the gut; it’s a source of useful butyrates. All fruits and vegetables contain useful fiber, but among those that provide food for butyrate production are asparagus, chicory, garlic, jerusalem artichoke, unripe bananas, leeks and onions.
Alpha lipoic acid is a powerful antioxidant fatty acid. It plays a role in supporting the health and function of the cardiovascular system, brain, nervous system, skin and muscles. It’s present in many foods (nuts and seeds, green vegetables) and in animal tissues. The body also can synthesize alpha lipoid acid from octanoic acid (caprylic acid), a constituent of mammal milk and some vegetable oils.
Lecithin, a fatty substance found in a variety of plants and animals, is a source of several valuable micronutrients, including choline, inositol and other glycerophospholipids and various lipids. It occurs naturally in almost all plant and animal food sources. Foods especially rich in lecithin include eggs, beans, fruit, grains, nuts, milk and seafood. It acts is a natural emulsifier in traditional recipes and is widely used in manufactured products.
Dangerous Fats
The fats that should have been banned many years ago are trans fats (or industrial trans-unsaturated fatty acids). Industrial trans fats cause inflammation throughout the body, especially in heart tissue. Consumption of industrial trans fats, even in small quantities, is known to increase the risk of coronary heart disease. It has no known health benefits. That’s why there is an effort, worldwide, to eliminate them from food products.
Industrial trans fats are manufactured. Starting usually with normal (healthy) vegetable oil, a process called hydrogenation changes the molecules to make them more stable and long-lasting. The benefits are entirely in the form of extended shelf life, which is why trans fats were used widely in processed and packaged food products. Margarine, vegetable shortening, processed vegetable oils and anything containing partially hydrogenated vegetable oil, contain industrial trans fats. Many processed foods and fried foods also contain some trans fats.
Fats That Might Be OK
There are two broad categories of fats that may be less damaging (overall) than previously thought: some saturated fats and natural trans fats.
Saturated fats are plentiful in many common foods, including all meats, whole milk, cheese, yogurt, butter and cream. They’re also present in coconut oil, palm oil and cocoa butter. Although most vegetable-based oils contain monounsaturated or polyunsaturated fats, many do contain a small amount of saturated oils. Human breast milk contains a high proportion of saturated fats, and for infants these saturated fatty acids provide energy and components vital to the efficient development of healthy brains and healthy bodies (nih.org). So, it’s unreasonable to suggest that all saturated fats are harmful. Adult human beings have been consuming saturated fatty acids for tens of thousands of years, at least. However, our ancient ancestors probably consumed small quantities—along with large quantities of fruits and vegetables, providing lots of antioxidants and fiber. It’s difficult to avoid all saturated fats—nor should we. Even the healthy Mediterranean diet contains some saturated fats.
We do know that saturated fat isn’t a uniquesubstance; in fact, there are numerous saturated fatty acids. As researchers identify the pathways in the body that these different substances follow, they find that some saturated fatty acids may be harmful, especially when consumed in large quantities. Othermay be more or less neutral, and others may even be beneficial. The picture is further complicated by the fact that foods that contain fatty acids also contain a cocktail of many other substances, so the net impact on the body is not easily predictable.
There is a debate in progress, with people lining up on both sides. Research results are conflicting, as illustrated by this report. These inconclusive results likely will lead to additional research and perhaps to a new perspective on the issue.
Natural trans fats which are not as dangerous as industrial trans fats. Our ancestors consumed trans fats in milk and meat products, but these were natural trans fats, not the dangerous industrial trans fats. Research on natural trans fats (in the form of conjugated linoleic acids, or CLA) suggests that they may not be as dangerous as the industrially manufactured version—and may even be beneficial, as suggested in this news report. So, like saturated fats, these natural trans fats might not be harmful in small quantities. That said, more research is needed to be sure.
In the meantime, it’s clear that overconsumption of animal-derived saturated fats,in general, is not good for human health. Excess consumption certainly raises bad cholesterol levels and is associated with weight gain, obesity, diabetes and cardiovascular disease. In small quantities, taken with plenty of vegetables andfruit(and with exercise added to the mix), animal fats may not be so bad. Perhaps.
Until we learn more, my advice is that adults should limit consumption of saturated fatty acids and natural trans fats (especially from red meat products) to a small proportion of calorie intake. Providing you eat plenty of vegetables and exercise regularly, it may not be necessary to eliminate every trace of these fats from our diets. Moderation rather than elimination should be your aim, as there are more important food priorities to consider.
Dr. Marc Ronert - Age Later 