* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download All About Fat and Cholesterol
Survey
Document related concepts
Calorie restriction wikipedia , lookup
Wilson's disease wikipedia , lookup
Waist–hip ratio wikipedia , lookup
Low-carbohydrate diet wikipedia , lookup
Epidemiology of metabolic syndrome wikipedia , lookup
Body fat percentage wikipedia , lookup
Adipose tissue wikipedia , lookup
Fat acceptance movement wikipedia , lookup
Abdominal obesity wikipedia , lookup
Diet-induced obesity model wikipedia , lookup
Human nutrition wikipedia , lookup
Transcript
All About Fat and Cholesterol SHINE Class 2 Port Townsend Chiropractic Bad Science The modern Western diet operates on the premise that a diet low in saturated fat and cholesterol, while high in carbohydrates and vegetable oils is healthy. There is actually minimal evidence to support this theory. Looking at other cultures and our own history it becomes clear that avoiding saturated fat and cholesterol is NOT the route to better health or weight loss. Why the confusion? Early studies looking at the dietary habits and health of different populations appeared to show a link between fat intake (especially saturated) and heart disease. Theoretically, this made a lot of sense: 1) Eat fat 2) Get fat 3) Develop fat related diseases Due to the serious nature of the study implications, the common sense it seemed to make, and the political weight of a few parties involved - this information quickly found its way to our government, television screens, newspapers, and magazines before it was adequately reviewed. Despite the fact that this early research turned out to have faulty methods and unwarranted conclusions, the idea that fat was bad had already gained momentum and provided a basis for future research and diet programs. Food for Thought “The assumption that fat makes people fat and causes heart disease makes sense, but that does not make it true.” - Robb Wolf, author of The Paleo Solution Diet and Health Trends in the US Before 1920 cardiovascular disease was nearly unheard of. Today it accounts for 40% of deaths in the US. What has changed in the last 80 years? - Dietary cholesterol intake has increased only 1%. - The percentage of dietary vegetable oils (think omega-6) in the form of margarine, shortening and refined oils increased about 400%. - The consumption of sugar and processed foods increased about 60%. - Overall fat consumption by Americans decreased by 21% between 1910 and 1970. So why do cardiovascular disease, diabetes, and obesity continue to plague our country? Learning from Other Cultures Review of dietary habits from populations in India, Italy, Puerto Rico, Japan, China, Greece, Yemen, and other cultures consistently showed that diets high in animal fat resulted in improved longevity and reduced rates of: - cancer - diabetes - heart disease - obesity - high cholesterol What the research is saying… The University of Maryland analyzed the data used to make claims that animal fat is linked not only with heart disease but also with cancers of various types. They found that vegetable fat consumption was correlated with cancer and animal fat was not. A survey of South Carolina adults found no correlation of blood cholesterol levels with "bad" dietary habits, such as eating red meat, animal fats, fried foods, butter, eggs, whole milk, bacon, sausage and cheese. And a Medical Research Council survey showed that men eating butter ran half the risk of developing heart disease as those using margarine. What the research is saying… In a multi-year British study involving several thousand men, half were asked to reduce saturated fat and cholesterol in their diets, stop smoking and increase the amount of unsaturated oils such as margarine and vegetable oils in their diet. After one year, men on the reduced saturated fat diet had twice as many deaths. A 40 year study conducted in the mid 1900’s in Framingham, Massachusetts found that the people who ate the most cholesterol, saturated fat, and calories, weighed the least and were the most physically active. They also noted that this group had the lowest serum cholesterol levels. Types of Fat – Saturated All carbon bonds are occupied by a hydrogen atom Highly stable due to their structure, so they typically do not go rancid, even when heated for cooking purposes Structure forms a solid or semisolid fat at room temperature Found in animal fats and tropical oils Types of Fat - Saturated Lauric Acid – found in coconut, palm oil, and breast milk. Known for its antiviral properties, including protection against HIV, chickenpox, CMV, and other viruses. It can help with reversing leaky gut and autoimmune issues. It can increase LDL, but is a non-issue if systemic inflammation is low and insulin levels are regulated by low carbohydrate intake. Populations consuming large amounts of lauric acid have higher LDL levels, but suffer little coronary vessel disease. Palmitic Acid – found in palm oil, beef, eggs, milk, poultry, and seafood. Also known to increase LDL levels, but is essential to the formation and recall of memories. Plays an important role in optimal cognitive function. Stearic Acid – found in meat, eggs, and chocolate. Neutral with respect to LDL levels, but increases HDL levels. It also decreases a marker of systemic inflammation (Apollo protein-A). Types of Fat - Unsaturated - - - Monounsaturated Fats have one double bond in the form of two carbon atoms doublebonded to each other and therefore, lacks two hydrogen atoms have a kink or bend at the position of the double bond so that they do not pack together as easily as saturated fats and tend to be liquid at room temperature they are relatively stable, do not go rancid easily and can be used - for some cooking - - - Polyunsaturated/ Essential Fats have two or more pairs of double bonds, lacking four or more hydrogen atoms the body cannot make these fatty acids and hence they are called "essential" and we must obtain them from the foods we eat they have multiple kinks at the position of the double bonds and do not pack together easily, and therefore are liquids even when refrigerated the unpaired electrons at the double bonds makes these oils highly reactive so they go rancid easily and should never be heated or used in cooking Types of Fat - Monounsaturated Oleic Acid – found mainly in plant sources, such as olive oil, avocado, and nuts. Associated with a host of health benefits, including improved insulin sensitivity, better liver function, blood sugar regulation, and decreased cholesterol levels. Typically plants sources of this fat are accompanied by antioxidants that prevent oxidative damage associated with aging and degenerative diseases! Types of Fat – Polyunsaturated/Essential Omega 3’s – found in flax, hemp, wild fish and game, and specific types of eggs. They have potent anti-inflammatory properties, decrease platelet aggregation, deter the spread of cancer, are critical for fetal brain development and normal, everyday cognitive function. Omega 6’s – found in vegetable oils (sunflower, safflower, cottonseed, corn, etc), animal products, and other oil (borage, primrose, etc). They are generally pro-inflammatory, regulate immune function and pain, and have roles in muscle repair, brain function, and exercise adaptation. It is not that omega 6 fats are inherently bad, they have important functions just like the omega 3 fatty acids. It is that typical diets today are overloaded with omega 6’s and deprived of omega 3 fats. This is a problem especially due to the pro-inflammatory nature of omega 6 fats. We need to find balance! Our ancestors had a 1:1 or 1:2 ratio of omega 3’s to 6’s. Today’s ratio have been conservatively calculated at 1:10 and much higher. Types of Fat – Cis vs Trans Fat In nature, fats are almost always found in the cis form, which means that both hydrogen atoms are on same side of the double bond. The bond can be chemically altered so that the hydrogen atoms are on opposite sides of the double bond, this makes it a trans fat. This is done to make oils that would be a liquid at room temperature into a solid or semi-solid form. It also makes the fats more stable, so that they do not go rancid as quickly. Avoiding Trans Fat Our metabolism has no idea what to do with trans fats. They ruin liver function, wreak havoc on blood lipids, and destroy insulin sensitivity. Looks for the words “partially hydrogenated”, “hydrogenated”, and “trans fat”. These fats/oils should not be consumed. Types of Fats - Chain Length - - - Short Chain Have four to six carbon atoms and are always saturated. These fatty acids have antimicrobial properties, protecting us from viruses, yeasts and pathogenic bacteria in the gut – they also contribute to the health of the immune system. They do not need to be acted on by the bile salts like larger fats, but are directly absorbed for quick energy. For this reason, they are less likely to cause weight gain than olive oil or commercial vegetable oils. Medium Chain Have eight to twelve carbon atoms and are found mostly in butterfat and the tropical oils. Like the short-chain fatty acids, these fats have antimicrobial properties and are absorbed directly for quick energy. They also contribute to the health of the immune system. Long Chain have from 14 to 18 carbon atoms and can be saturated, monounsaturated, or polyunsaturated. Why We Need Fat (in particular saturated fat) Saturated fatty acids constitute at least 50% of cell membranes. They are what gives our cells necessary stiffness and integrity. They play a vital role in the health of our bones. For calcium to be effectively incorporated into the skeletal structure, at least 50% of the dietary fats should be saturated. They lower Lp(a), a substance in the blood that indicates vulnerability to heart disease. They protect the liver from alcohol and other toxins, such as over the counter and prescription drugs. They enhance the immune system. They are needed for the proper utilization of essential fatty acids. Elongated omega-3 fatty acids are better retained in the tissues when the diet is rich in saturated fats. Saturated 18-carbon stearic acid and 16-carbon palmitic acid are the preferred foods for the heart, which is why the fat around the heart muscle is highly saturated. The heart draws on this reserve of fat in times of stress. Short- and medium-chain saturated fatty acids have important antimicrobial properties. They protect us against harmful microorganisms in the digestive tract. Getting Clear on Cholesterol Cholesterol is a substance made predominately in the liver, but in most other cells in the body as well. Cholesterol is neither good or bad, it is simply a substance that is present in the body and serves a variety of functions…also consider why the body would make something if it is inherently bad for it? Types of Cholesterol High-density lipoprotein (HDL): carries lipids and cholesterol from the periphery of the body back to the liver, helping to keep cholesterol away from arteries and removing any excess from arterial plaques, which may help to prevent heart disease. Low-density lipoprotein (LDL): circulates in the blood carrying cholesterol and lipids to tissues that require them. There is some correlation between LDL levels and risk of heart disease, however the link is not a direct causal relationship. Very low-density lipoprotein (VLDL): similar function to LDL, however they give rise to reactive LDL’s that tend to get stuck on the lining of the arteries causing the damage that leads to atherosclerosis. While dietary fat does influence our LDL levels, the main source of reactive LDL’s is high-carbohydrate intake. What Type of Cholesterol Is Unhealthy? Conventional cholesterol testing measures the total cholesterol and the number of HDL particles in your blood. This gives you a ratio of LDL to HDL. (LDL and VLDL are calculated, not actually measured) A more useful level to test is the triglyceride level, which has better evidence to link it to heart disease. Current research indicates that it is actually a subset of LDL particles (those particles smallest in size) that are most likely to cause heart disease. Tests are being developed to measure this specific subset of cholesterol molecules, but this is not typically offered. Functions of Cholesterol Along with saturated fats, cholesterol in the cell membrane gives our cells necessary stiffness and stability. When the diet contains an excess of polyunsaturated fatty acids, these replace saturated fatty acids in the cell membrane, so that the cell walls actually become weak, this has a variety of biochemical implications. When this happens, cholesterol from the blood is "driven" into the tissues to give them structural integrity. This is why serum cholesterol levels may go down temporarily when we replace saturated fats with polyunsaturated oils in the diet. It acts as a precursor to vital corticosteroids, which are hormones that help us deal with stress and protect the body against heart disease and cancer. Cholesterol is also a precursor to the sex hormones like androgen, testosterone, estrogen and progesterone. It is a precursor to vitamin D, a very important fatsoluble vitamin needed for healthy bones and nervous system, proper growth, mineral metabolism, muscle tone, insulin production, reproduction and immune system function. Bile salts are made from cholesterol. Bile is vital for digestion and assimilation of fats in the diet. Functions of Cholesterol, Cont. Cholesterol acts as an antioxidant and antiinflammatory. This may be the explanation for the fact that cholesterol levels go up with age. As an antioxidant, cholesterol protects us against free radical damage that leads to heart disease and cancer. It is needed for proper function of serotonin receptors in the brain. Serotonin is the body's natural "feel-good" chemical. Low cholesterol levels have been linked to aggressive and violent behavior, depression and suicidal tendencies. Mother's milk is especially rich in cholesterol and contains a special enzyme that helps the baby utilize this nutrient. Babies and children need cholesterol-rich foods throughout their growing years to ensure proper development of the brain and nervous system. Dietary cholesterol plays an important role in maintaining the health of the intestinal wall. This is why lowcholesterol vegetarian diets can lead to leaky gut syndrome and other intestinal disorders. Dangers of Low Cholesterol - The push for low cholesterol levels and the use of statin drugs has a back story of politics, financial ties, and murky science. To keep things simple, lets just say that the motives for lowering cholesterol appear less than pure and we should always investigate matters affecting our own health. Risk of having cholesterol levels that are too low: Increased risk of depression and violent behavior. Insufficient production of vitamin D, sex hormones, and corticosteroids. Increased risk of heart disease. Possible link to the development of cancer and Parkinson’s disease. Just to name a few… Keeping cholesterol levels healthy The vast majority of people can control their cholesterol levels naturally, a rare exception is when there is a strong genetic component. Natural means to keeping cholesterol levels healthy includes the following: - Eat plenty of high-quality, animal-based omega 3 fats. - Reduce, with the plan of eliminating, grains and sugars in your daily diet. - Eat a good portion of your food raw. - Eat healthy, preferably raw, fats including olive oil, coconut oil, organic raw dairy products, avocados, raw nuts, seeds, eggs, organic, grass-fed meats. - Get a healthy amount of exercise. When you exercise you increase your circulation and the blood flow throughout your body. The components of your immune system are also better circulated, which means your immune system has a better chance of fighting an illness before it has the opportunity to spread. - Avoid smoking and drinking excessive amounts of alcohol. - Address emotional challenges and stressors in a healthy way. In Summary The cause of disease is NOT saturated animal fats and cholesterol but instead a number of factors inherent to our modern diets and lifestyles. These include: - Excess consumption of vegetables oils, oxidized and hydrogenated fats, and refined carbohydrates in the form of sugar and white flour. - Mineral and vitamin deficiencies. - The disappearance of antimicrobial fats from the food supply, namely, animal fats and tropical oils. These once protected us against the kinds of viruses and bacteria that have been associated with the onset of pathogenic plaque leading to heart disease. - A sedentary lifestyle, smoking, and environmental stressors.