The Big Fat Myth

It’s easy to find ready sources that say dietary fat is bad news. Many clinicians still hold that saturated fats like coconut oil, butter and beef cause weight gain, clogged arteries, high cholesterol and heart disease. But, what if it it’s time to re-evaluate fat’s bad reputation? This blog will fill you in on the research and debunks one of the big myths still surrounding this well-known macronutrient.

Myth: Saturated Fat and Cholesterol Increases Risk of Heart Disease

Today, many doctors still tell their patients to limit saturated fat and cholesterol intake (found in red meats, butter, eggs and oils like palm and coconut) and recommend a statin drug when their cholesterol is over 200 mg/dL. This is probably due in part to misleading evidence that suggested that cholesterol levels are directly correlated to risk of heart disease. One such study was performed by a researcher by the name of Ancel Keys in the 1980’s that looked at 22 countries and found that dietary fat intake was related to increased risk of heart disease. However, data on only 7 of those 22 countries was published – those that fit his hypothesis. Since then, many researchers and physicians have refuted this study, and yet, the recommendations that come down the pipe from the American Heart Association and the USDA continue to perpetuate that dietary fat and cholesterol are bad for us.

Research has and continues to show that high quality animal fats and eggs aren’t the real culprit in heart disease. One of the most notable studies that shows this was called the Women’s Health Initiative, which studied over 48,000 postmenopausal women and the connection between a low fat diet and the risk of heart disease. After a mean of 8 years, the group that reduced overall fat intake and increased intake of whole grains, fruits and vegetables did not experience reduced risk of CHD, stroke or CVD over the control group. There are other studies that have found similar results, indicating that low fat diets don’t really have much impact on heart disease risk. A report published in 2010 by the American Journal of Clinical Nutrition stated that there was no substantiated link between saturated fat intake and outcomes of obesity, CVD, cancer or osteoporosis. And, if you need even more proof, a meta-analysis of 21 medical reports and studies also published in 2010 in the American Journal of Clinical Nutrition concluded that, “the intake of saturated fat was not associated with an increased risk of coronary heart disease, stroke or CVD.”

If not fat, then what?

So, if saturated fats aren’t the culprit in CVD and atherosclerosis, then what is? Enter carbohydrates. Most grains and sugars are highly inflammatory. As a society, our diets are high in processed and packaged foods like pastries, fast food, crackers, cookies and cakes. Eating these foods causes surges in blood sugar and taxes the pancreas, whose job it is to produce insulin to shuttle the sugar into our cells to be used for energy or stored for later. Over time, the cells become resistant to insulin and sugar remains in the bloodstream instead of being transported into the cells. Sugar in the blood stream sticks to protein molecules like LDL cholesterol (called “bad cholesterol”). This changes the structure of the LDL and causes an inflammatory cascade which leads to plaques in the arteries and the inability of LDL to carry cholesterol where it’s needed, especially to the brain. So, now we have a simple equation. Too many carbohydrates cause inflammation, which leads to oxidized or damaged LDL and atherosclerosis. This is what leads to heart disease, not eating too much dietary saturated fat and cholesterol.

What are the benefits of a high fat diet?

So, what does the science tell us about a high fat diet? Research is showing that a high fat, low carbohydrate diet is beneficial for:

  • Heart health
  • Boosting the immune system
  • Brain function (and reduced risk of Alzheimer’s, cognitive impairment and dementia)
  • Blood sugar control
  • Weight management


High fat diets, and even ketogenic diets are being studied for their efficacy in treating Parkinson’s, Alzheimer’s, ALS, Epilepsy and even ADHD. In particular, cholesterol is especially protective of brain function. One famous study called the Framingham Heart Study found that those with low serum cholesterol performed less well on cognitive function tests than their counterparts with borderline or high cholesterol levels. We can deduct from that that cholesterol has a protective effect on the brain. (On a side note, think of the ramifications for those who take a statin drug to lower cholesterol. One known side effect of statin drugs is problems with memory and cognition.)

What should I eat?

The good news is that it’s easy to start enjoying the benefits of a high fat, low carb diet. It’s important to limit large portions of grains and legumes to maintain the benefits. Try to aim for only about 60 grams of carbohydrates a day. Along with unlimited non-starchy vegetables (think asparagus, cauliflower, broccoli, kale, swiss chard and spinach) and low sugar fruits (grapefruits, oranges, apples, berries, melon, pears, cherries, grapes, kiwis, plums, peaches and nectarines), enjoy these foods to experience the benefits of a high fat diet:

  • Grass fed beef and lamb
  • Free range chicken
  • Cage free eggs
  • Cold pressed oils (walnut, olive, avocado, coconut, and palm)
  • Grass fed butter
  • Cold water fish (salmon, shrimp, sardines and tuna)
  • Nuts (walnut, cashews, macadamia and almonds)
  • Avocados
  • Cheese (Gruyere, goat cheese, feta cheese, and mozzarella)



Sample One Day  High Fat Meal Plan*


2 scrambled eggs with 1 oz. goat cheese cheese and stir fried veggies (onions, mushrooms, spinach and red bell pepper)


4 oz. baked chicken or canned tuna with a side of leafy greens dressed in balsamic and olive oil


3 oz. grass fed steak with a side of roasted broccoli and mashed cauliflower


3 squares of 70% dark chocolate

*Adapted from Dr. David Perlmutter’s book Grain Brain


Different Strokes for Different Folks

 Does this mean that high fat diets are for everyone?  Not necessarily.  High fat and very low carb diets still have their downfalls.  These diets tend to be much lower in fiber, which in return can affect our digestive system and microbiome.  Specific fibers we get from foods such as lentils, bananas, plantains, oats and other beans provide prebiotics that are fermented into short chain fatty acids (SCFA), which provide a source of fuel for colon cells (colonocytes) leading to a healthy well-balanced microbiome.  Our microbiome is key to overall health, therefore, providing it with fuel to feed the healthy bacteria in our guts is incredibly important.

The bottom line, it is about balance.  Balance in one’s life and balance on our plates.  The important message here is to not fear fat.  Fat is an incredibly important macronutrient that is crucial to our health.  However, balance of all nutrients may be just the right fit for you.

We are here to help!  If you are looking for guidance and help in understanding nutrition for your body, give us a call!

For more recipes, check out our website!



Contributed by Elizabeth McKinney, MS, CNS, LDN, CLT

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