Preventable, non-communicable diseases account for more deaths worldwide today than all other diseases combined.” – New England Journal of Medicine
Let’s talk about food . . .
Historically, or since commercial food marketers, most of what we’ve been told about what to eat is not only confusing but sometimes deadly. For example, in the 80s the food boogeymen, we were told, were fats and cholesterols. Eggs and butter were out, non-fat yogurt and pretzels were in. Interestingly enough that low fat craze was followed by a historic increase in heart disease, obesity, type 2 diabetes, and brain diseases like dementia and Alzheimer’s. The “nutrition experts” of the time were so convincing with their motto of “eating fat makes you fat”, though, that people to this day feel guilty if they don’t buy skim milk and other low fat products. What some of us are learning, however, is that healthy fats are essential to the functioning of the all the cells of the body and to the brain and that what causes weight gain and fat retention are carbohydrates and sugars. (More about sugars and how, in excess, they change our bodies.)
Let’s talk about fats . . .
Fats have always played an essential role in human nutrition. For example, fat is pivotal in regulating our immune systems. Also, the brain is 70% fat. And 50% of the membranes of all of our cells consist of cholesterol. Good fats, like omega-3s and monounsaturated fats, reduce inflammation. While modified hydrogenated (heated fats), so common in commercially prepared foods, dramatically increase inflammation. In addition, certain vitamins, notably A, D, and E, require fat to get absorbed properly, which is why dietary fat is necessary to transport these “fat soluble” vitamins. (Because these vitamins do not dissolve in water, they can only be absorbed from your small intestine in combination with fat. Deficiencies due to incomplete absorption of these vitally important nutrients are serious.)
If you follow the convention of the day, you know you are only suppose to get 20% of your calories from fats, and only 10% of that number from saturated fats. What the research shows is that is misguided advice. Synthetic trans fats are poisonous, but the fats found in foods such as raw nuts, seeds like flax seeds and chia, cold-water fish, olives, and avocados are healthy in much larger amounts. Our bodies actually require healthy forms of saturated fats like that found in coconut oil.
Let’s talk about saturated fats . . .
Saturated fats play an important role in most biochemical processes. They also contribute to the structure and function of your lungs, heart, bones, liver, and immune system. Lungs require fats to make surfactant, a lubricant that allows us to breathe. Heart muscle cells use saturated fats as food. And bone cells require saturated fats to assimilate calcium effectively. With the help of good saturated fats, your liver clears out fats and protects you from the adverse effects of toxins, including alcohol and compounds in medications. The white blood cells of your immune system owe their ability to recognize and destroy invading germs as well as fighting tumors to the fats found in butter and coconut oil. Even our endocrine systems rely on saturated fats to communicate the need to manufacture hormones, including insulin.
And what about cholesterol?
If you’ve had your cholesterol checked you’ve probably heard about HDL (high-density lipoprotein—the so-called good fats) and LDL (low-density lipoprotein—the so-called bad fats). Contrary to what you’ve been told these are not two different kinds of cholesterol. HDL and LDL reflect two different containers for cholesterols and fats, each of which serves an important and different role in the body. Other lipoproteins exist, but that is a subject for another blog . . .
Cholesterol offers a level of protection against free radical damage, forms the cellular membrane, keeps cell membranes permeable, and maintains cellular waterproofing so different chemical reactions can take place inside and outside the cell. We have even determined that the ability to grow new synapses in the brain depends on the availability of cholesterol, which latches cell membranes together so that signals can easily jump across the synapse. And it is also crucial to the myelin sheathing around neurons. A neuron that can’t transmit messages is cast aside like junk—the debris of which is one of the markers of brain disease.
The Cholesterol Myth
Most of us grew up being told that cholesterol was bad and that foods like red meat, butter, and eggs raise our cholesterol levels. This idea is so deeply ingrained in our cultural psyche that few people even question it. But is it really true? The diet-heart hypothesis—which holds that eating cholesterol and saturated fat raises cholesterol in our blood—originated with studies in both animals and humans more than half a century ago. However, more recent evidence doesn’t support it. (I should also note here that we have altered the chemistry and quality of our meat and dairy products through industrialization and feeding them corn and soy—there is both more fat in these products and the kind of fat is inferior.)
On any given day, we have between 1,100 and 1,700 milligrams of cholesterol in our body. 25% of that comes from our diet, and 75% is produced inside of our bodies by the liver. Much of the cholesterol that’s found in food can’t be absorbed by our bodies, and most of the cholesterol in our gut was first synthesized in body cells and ended up in the gut via the liver and gall bladder. The body tightly regulates the amount of cholesterol in the blood by controlling internal production; when cholesterol intake in the diet goes down, the body makes more. When cholesterol intake in the diet goes up, the body makes less.
This explains why well-designed cholesterol studies (where they feed volunteers 2-4 eggs a day and measure their cholesterol) show that dietary cholesterol has very little impact on blood cholesterol levels in about 75% of the population. The remaining 25% of the population are referred to as “hyper-responders”. In this group, dietary cholesterol does modestly increase both LDL and HDL, but it does not affect the ratio of LDL to HDL or increase the risk of heart disease.
In other words, eating cholesterol isn’t going to give you a heart attack. You can ditch the egg-white omelets and start eating yolks again—if your body is not allergic or reactive to eggs, which you can test for. (A word on egg yolks: all of the 13 essential nutrients eggs contain are found in the yolk. Egg yolks are an especially good source of choline, a B-vitamin that plays important roles in everything from neurotransmitter production to detoxification to maintenance of healthy cells. Studies show that up to 90% of Americans don’t get enough choline, which can lead to fatigue, insomnia, poor kidney function, memory problems and nerve-muscle imbalances.)
Studies on low-carbohydrate diets (which tend to be higher in saturated fat) suggest that they not only don’t raise blood cholesterol, they have several beneficial impacts on cardiovascular disease risk markers. For example, an analysis of 17 low-carb diet trials covering 1,140 obese patients published in the journal, Obesity Review, found that low-carb diets neither increased nor decreased LDL cholesterol. However, they did find that low-carb diets were associated with significant decreases is body weight as well as improvements in several cardio vascular risk factors, including decreases in triglycerides, fasting glucose, blood pressure, body mass index, abdominal circumference, plasma insulin and c-reactive protein.
If you’re wondering whether saturated fat may contribute to heart disease in some way that isn’t related to cholesterol, a large analysis of studies involving close to 350,000 participants found no association between saturated fat and heart disease. A Japanese study that followed 58,000 men for an average of 14 years found no association between saturated fat intake and heart disease, and an inverse association between saturated fat and stroke (i.e. those who ate more saturated fat had a lower risk of stroke!).