What’s Worse Saturated Fat or Sugar?

What Causes Fatty Liver Disease?

Author: Dr. Stephen Chaney

 

what is worse saturated fats or sugarThe great American food fight continues. The low fat enthusiasts tell you saturated fat is going to kill you. The low carb enthusiasts tell you saturated fat is fine. It’s sugar that’s going to kill you.

You can find studies that support either viewpoint. And the story keeps changing. One day the headlines proclaim: “The latest study shows…” A few weeks later you see a headline saying: “Wait. That’s wrong. Science now shows…” It’s no wonder you are confused and perhaps a bit cynical.

So, what’s worse saturated fat or sugar?

Perhaps we should step back and ask how we got to this point.

 

Why Is the Saturated Fats and Sugar Dilemma So Confusing?

saturated fats or sugar dilemmaTo understand why the literature around saturated fats and sugar is so confusing, we need to go back to the 1950s. The first studies implicating saturated fats as a risk factor for heart disease replaced saturated fats with unsaturated fats. Everything else in the diet was kept the same. When you do that, the answer is clear-cut. Saturated fats increase heart disease risk and unsaturated fats decrease heart disease risk.

When the American Heart Association first recommended a low-fat diet, they had in mind replacing saturated fats with fresh fruits, vegetables, whole grains, and beans. The remaining fat would be mostly unsaturated. Today, we would call that a Mediterranean diet, which, by the way, has been shown to reduce both diabetes and heart disease risk.

Big Food Inc. took one look at that and panicked. They make their money from processed foods, not from fresh fruits and vegetables. If the American people made the changes the American Heart Association recommended, Big Food Inc. would go bankrupt.

They sprang into action. They had their laboratories whip up processed foods that replaced fat with sugar, white flour, and a witch’s brew of chemicals. Then they told the American people: “Never fear. You don’t have to give up your favorite foods. We have created low fat versions of the foods you love.”

That became the diet that most Americans adopted. Even worse, most Americans continued eating foods high in saturated fats. We ended up with the worst of all possible worlds – a diet high in saturated fat and high in sugar. This became the Standard American Diet (SAD).

This shift has corrupted most of the recent research studies on saturated fat and sugar. Most of the studies on saturated fat or sugar have compared them with the Standard American Diet, not with a healthy diet. When you do that, your results are going to be skewed. Almost anything is better that the Standard American Diet.

Why Was This Study Done?

fatty liver disease causesWhen we think of obesity, we think of the excess fat we can see. But what we have learned in recent years is that the fat you can’t see is far more damaging to our health. I am talking about fat stores in the liver, something called fatty liver disease.

Fatty liver disease has serious consequences. It causes insulin resistance and inflammation, and that increases the risk of diabetes and heart disease. Even worse, it can lead to cirrhosis and liver failure.

Excess sugar is converted to saturated fat in the liver. Therefore, the popular literature attributes the epidemic of fatty liver disease to increased intake of simple sugars. But is it true? Saturated fats require no conversion. They can simply be deposited in the liver as is. Shouldn’t they be at least as damaging to the liver as sugar?

It turns out that no studies have actually compared the effect of excess calories in the form of saturated fat, unsaturated fat, and simple sugars on fat accumulation in the liver. This study (PK Luukkonen et al, Diabetes Care, 41: 1732-1739, 2018) was designed to fill that gap.

How Was The Study Done?

saturated fats or sugar studyThe authors enrolled 38 middle aged (average age = 48), overweight (average BMI = 31) adults for the study. The participants were divided into three groups and were fed an extra 1,000 calories per day of saturated fat (SAT group), unsaturated fat (UNSAT group), or sugar (SUGAR group) for 3 weeks. The composition of those extra 1,000 calories was as follows:

  • The SAT group ate an extra 30 g coconut oil, 40 g butter, and 100 g blue cheese
    • Macronutrient composition = 1% carbohydrate, 86% fat, 13% protein, 0% simple sugars.
    • Fat composition = 76% saturated fats, 21% monounsaturated fats, 3% polyunsaturated fats
  • The UNSAT group ate an extra 36 g olive oil, 26 g pesto, 54 g pecans, and 20 g butter
    • Macronutrient composition = 2% carbohydrate, 91% fat, 7% protein, 0% simple sugars.
    • Fat composition = 21% saturated fats, 57% monounsaturated fats, 22% polyunsaturated fats
  • The SUGAR group ate an extra 9.5 ounces of orange juice, 16 ounces of sugar-sweetened beverages, and 200 g of candy.
    • Macronutrient composition = 100% simple sugars.

Compliance to these dietary additions was confirmed by measuring the fat composition of serum triglycerides. As expected, the triglycerides were primarily composed of saturated fat in the SAT and SUGAR groups and unsaturated fats in the UNSAT group.

None of the participants had diabetes or other diseases, pre-existing liver disease, excessive consumption of alcohol (which can also lead to fatty liver disease). They were also not taking any drugs that could influence glucose or lipid metabolism.

Upon entry into the study, the three groups were comparable with respect to age, sex, BMI (a measure of obesity), amount and type of fat stores in the liver, and insulin sensitivity.

The baseline diet to which the extra calories were added was also comparable between the three groups and did not change during the study. That meant that the only difference between groups was the composition of the extra calories they consumed.

 

What Causes Fatty Liver Disease?

fatty liver disease dietsAt the end of three weeks:

  • All 3 groups gained weight, but the weight gain was slightly larger (0.6 pounds) for the SAT and SUGAR groups than for the UNSAT group (0.4 pounds).
  • Fat stores in the liver increased by 55% in the SAT group, 33% in the SUGAR group, and 15% in the UNSAT group.
  • The fat stores were primarily saturated fat in the SAT and SUGAR groups and primarily unsaturated fat in the UNSAT group.
  • Insulin resistance was increased in the SAT group, but not in the SUGAR and UNSAT groups.

Previous studies have suggested that the effect of liver fat stores on insulin resistance might be mediated by fat metabolites called ceramides. Therefore, they also measured plasma ceramide levels.

  • Plasma ceramides were increased in the SAT group, but not in the SUGAR and UNSAT groups.

Previous studies have also suggested that the effect of saturated fat on insulin resistance might be mediated by a change in gut bacteria that produce endotoxins which end up in the bloodstream.

  • A change in gut bacteria and an increase in plasma endotoxins was observed in the SAT group, but not in the SUGAR and UNSAT groups.

 

What is Worse Saturated Fat Or Sugar?

sugar cubesThe authors of this study concluded: “Saturated fat induced the greatest increase in fat stores in the liver, insulin resistance, and harmful ceramides. Decreased intakes of saturated fat could be beneficial in reducing fat stores in the liver and the associated risk of diabetes.”

Is that statement true? This study was well designed. However, this is a very small study. It needs to be replicated by larger studies. In the meantime, we can ask if the findings are consistent with previous studies.

You may have noticed, the authors included three variables in their study (saturated fats, unsaturated fats, and simple sugars), but I focused only on the comparison between saturated fats and simple sugars in this article. That is because the damage caused by saturated fats versus simple sugars is controversial in the popular literature. In contrast, most (but not all) experts agree that saturated fats are worse for you than unsaturated fats.

Let’s start with the relatively non-controversial comparison (saturated fats versus unsaturated fats) before turning to the comparison between saturated fats and simple sugars. When comparing saturated fats and unsaturated fats, the author’s conclusion that saturated fats are worse for you is probably true.

  • In this study saturated fats caused greater fat accumulation in the liver than unsaturated fats, and these differences were statistically significant.
  • The fat stores in the liver mirrored the fat composition of the diet. Saturated fat caused saturated fat stores. Unsaturated fat caused unsaturated fat stores.
  • Saturated fats increased insulin resistance while unsaturated fats did not.
  • This is consistent with several previous studies that have shown:
  • Saturated fats cause greater fat accumulation in the liver than polyunsaturated fats in younger, normal weight individuals.
  • High saturated fat intake is associated with fatty liver disease and insulin resistance.
  • Saturated fat increases heart disease risk, while unsaturated fat decreases heart disease risk.

However, the differences between saturated fats and sugar were less clear.

  • In this study saturated fats caused greater fat accumulation in the liver and more insulin resistance than simple sugars.
  • The conclusion that saturated fats are worse for you than simple sugars was strengthened by the following:
  • Saturated fat caused insulin resistance, while simple sugars did not.
  • Saturated fat caused a change to gut bacteria which resulted in increased endotoxin levels in the bloodstream, while simple sugars did not.
  • The conclusion that saturated fats are worse for you than simple sugars was weakened by the following:
  • The difference in fat accumulation in the liver was not statistically significant. A larger study may have provided a more definitive answer.
  • Previous studies have suggested that saturated fats and simple sugars may be equally bad for you. They both increase the risk of diabetes and heart disease.

Clearly, this study does not end the debate about whether saturated fats or simple sugars are worse for you. However, it does provide a new perspective.

Previous studies have not compared the effects of saturated fat and sugar on fatty liver disease when all other aspects of the diet were identical. If the observations of this study are confirmed in subsequent studies, it could influence how we evaluate the relative risks of saturated fats and sugars in the future.

What Does This Study Mean For You?

When you strip away all the noise, there are three obvious conclusions from this and most previous studies:

  • Excess calories in any form are bad for us. We don’t just store fat in the liver, and fat stores in other parts of our body have bad effects on our health as well.
  • Unsaturated fats are better for us than saturated fats. They reduce the risk of heart disease. This study suggests they also reduce the risk of fatty liver disease, insulin resistance, and possibly diabetes.
  • The jury is still out on the health consequences of saturated fats versus simple sugars. This study suggests that simple sugars may be less likely to cause fatty liver disease. While fatty liver disease can lead to diabetes and heart disease, so can fat stores anywhere else in the body. Other studies suggest that excess calories as saturated fats and simple sugars are equally likely to lead to obesity, diabetes and heart disease.

My recommendation is to avoid both saturated fats and simple sugars. Don’t focus on low fat diets or low carb diets. Instead focus on whole food diets with healthy fats and healthy carbs.

 

The Bottom Line

 

Fatty liver disease has serious consequences. It causes insulin resistance and inflammation, and that increases the risk of diabetes and heart disease. Even worse, it can lead to cirrhosis and liver failure.

Excess sugar is converted to saturated fat in the liver. Therefore, the popular literature attributes the epidemic of fatty liver disease to increased intake of simple sugars. But is it true? Saturated fats require no conversion. They can simply be deposited in the liver as is. Shouldn’t they be at least as damaging to the liver as sugar?

A recent study compared the effect of diets high in saturated fats (SAT group), unsaturated fats (UNSAT group), or simple sugars (SUGAR group) on fat accumulation in the liver. The results were:

  • Fat stores in the liver increased by 55% in the SAT group, 33% in the SUGAR group, and 15% in the UNSAT group.
  • The fat stores were primarily saturated fat in the SAT and SUGAR groups and primarily unsaturated fat in the UNSAT group.
  • Insulin resistance was increased in the SAT group, but not in the SUGAR and UNSAT groups.

The authors of this study concluded: “Saturated fat induced the greatest increase in fat stores in the liver and insulin resistance. Decreased intakes of saturated fat could be beneficial in reducing fat stores in the liver and the associated risk of diabetes.”

My recommendation is to avoid both saturated fats and simple sugars. Don’t focus on low fat diets or low carb diets. Instead focus on whole food diets with healthy fats and healthy carbs.

For more details on the study and what it means for you, read the article above.

 

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

Should You Avoid Sugar Completely?

Is It The Sugar, Or Is It The Food?

Author: Dr. Stephen Chaney

 

Should we avoid sugar completely?  Almost every expert agrees that Americans should cut down on the amount of sugar we are consuming. However, for some people this has become a “sugar phobia”. They have sworn that “sugar shall never touch their lips”. Not only do they avoid sugar sweetened sodas and junk food, but they also have become avid label readers. They scour the label of every food they see and reject foods they find any form of sugar listed as an ingredient. Is this degree of sugar avoidance justified?

 

Should We Avoid Sugar to Keep it From Killing Us?

 

Let me add some perspective:

  • If you just take studies about the dangers of sugar at face value, sugar does, indeed, look dangerous. Excess sugar consumption is associated with increased risk of obesity, diabetes, and heart disease. However, when you look a little closer, you find that most of these studies have been done by looking at the correlation of each of these conditions with sugar sweetened beverage consumption (sodas and fruit juices).

A few studies have looked at the correlation of obesity and disease with total “added sugar” consumption. However, 71.6% of added sugar in the American diet comes from sugar sweetened beverages and junk food. None of the studies have looked at the sugar from healthy foods like fruits, vegetables, and whole grains. That’s because there is ample evidence that these foods decrease the risk of obesity, diabetes, and heart disease.

  • For example, if apples had a nutrition label, it would list 16 grams of sugar in a medium 80 calorie apple, which corresponds to about 80% of the calories in that apple. The sugar in an apple is about the same proportion of fructose and glucose found in high fructose corn syrup. Apples are not unique. The nutrition label would read about the same on most other fruits. Does that mean you should avoid sugar from all fruits? I think not.

Avoid Sugar or Avoid Certain Foods

 

avoid sugar from junk foodsThe obvious question is: “Why are the same sugars, in about the same amounts, unhealthy in sodas and healthy in fruits?” Let’s go back to those studies I just mentioned—the ones that are often used to vilify sugars. They are all association studies, the association of sugar intake with obesity and various diseases.

The weakness of association studies is the association could be with something else that is tightly correlated with the variable (sugar intake) that you are measuring. Could it be the food that is the problem, not the sugar?

If we look at healthy foods (fruits, vegetables, whole grains) they are chock full of vitamins, minerals, phytonutrients, fiber, and (sometimes) protein. Fiber and protein slow the absorption of sugar into the bloodstream. As a result, blood sugar levels rise slowly and are sustained at relatively low levels for a substantial period of time.

In sodas there is nothing to slow the absorption of blood sugar. You get rapid rise in blood sugar followed by an equally rapid fall. The same is true of junk foods consisting primarily of sugar, refined flour and/or fat.  Avoid sugar from those types of foods.

Another consideration is something called caloric density. Here is a simple analogy. I used to explain the concept of caloric density to medical students in my teaching days. There are about the same number of calories in a 2-ounce candy bar and a pound of apples (around 278 in the 2-ounce candy bar and 237 in a pound of apples). You can eat a 2-ounce candy bar and still be hungry. If you eat a pound of apples you are done for a while. In this example, the 2-ounce candy bar had a high caloric density (a lot of calories in a small package). Perhaps a more familiar terminology would be the candy bar was just empty calories.

Are Sodas and Junk Foods Killing Us?

avoid sugar from candyPutting all that together, you can start to understand why the foods the sugars are in are more important than the sugars themselves. When you consume sugars in the form of sugar sweetened beverages or sugary junk foods, your appetite increases. We don’t know for sure whether it is the intense sweetness of those foods, the rapid increase and fall in blood sugar, or the high caloric density (lots of calories ina small package) that makes us hungrier. It doesn’t matter. We crave more food, and it isn’t usually fruits, vegetables, and complex carbohydrates we crave. It’s more junk. That sets in motion a predictable sequence of events.

  • We overeat. Those excess calories are stored as fat and we become obese. [Note: The low carb enthusiasts will tell you our fat stores come from carbohydrates alone. That is incorrect. All excess calories, whether from protein, fat, or carbohydrate, are stored as fat.]
  • It’s not just the fat you can see (belly fat) that is the problem. Some of that fat builds up in our liver and muscles. This sets up an unfortunate sequence of metabolic events.
  • The fat stores release inflammatory cytokines into our bloodstream. That causes inflammation. Inflammation increases the risk of many diseases including heart disease and cancer.
  • The fat stores also cause our cells to become resistant to insulin. That reduces the ability of our cells to take up glucose, which leads to hyperglycemia and type 2 diabetes. [Note: The low carb enthusiasts will tell you carbohydrates cause type 2 diabetes. That is also incorrect. It is our fat stores that cause insulin resistance and type 2 diabetes. Our fat stores come from all excess calories, not just excess calories from carbohydrates.]
  • Insulin resistance also causes the liver to overproduce cholesterol and triglycerides and pump them into the bloodstream. That increases the risk of heart disease.
  • Sugar sweetened beverages and sugary junk foods also displace healthier foods from our diet. That leads to potential nutrient shortfalls that can increase our risk of many diseases.

However, none of this has to happen. The one thing that every successful diet has in common is the elimination of sodas, junk foods, fast foods and convenience foods. You should avoid sugar from those foods as much as possible. Once you eliminate those from your diet,you significantly enhance your chances of being at a healthy weight and being healthy long term.

 

What About Protein Supplements And Similar Foods?

Of course, the dilemma is what you, as an intrepid label reader, should do about protein supplements, meal replacement bars, or snack bars. They are supposed to be healthy, but the label lists one or more sugars. Even worse, the sugar content is higher than your favorite health guru recommends.  So, should you avoid sugar from supplements and the like?

In this case, a more useful concept is glycemic index, which is a measure of the effect of the food on your blood sugar levels. Healthy foods like apples may have a high sugar content, but they havea low glycemic index.

avoid sugar and consume protein to slow absorbptionThe same is true for the protein supplements and bars you are considering. Rather than looking at the sugar content, you should be looking for the term “low glycemic” on the label. That means there is enough fiber and protein in the food to slow the absorption of sugar into the bloodstream and stabilize your blood sugar levels.

What Does This Mean For You?

Don’t misunderstand me. I am not advocating for unlimited consumption of sugar. We should work on ways to avoid sugar or reduce the amount of sugar in our diet. On the other hand, we don’t need to become so strict that we and our family need to eat foods that taste like cardboard. We also don’t want to replace natural sugars with artificial sweeteners. I have warned about the dangers of artificial sweeteners previously.

We can go a long way towards reducing sugar by just eliminating sodas, other sugar sweetened beverages, junk foods, fast foods, convenience foods, and pastries from our diet. When considering fast foods and convenience foods, we should check the label for hidden sugar. For example, some Starbucks drinks are mostly sugar. When considering foods that are supposed to be healthy, we should look for the term “low glycemic” on the label.

So we don’t have to avoid sugar completely, but we should reduce sugar from sugar sweetened beverages and junk food.

 

The Bottom Line

 

We need to keep warnings about the dangers of sugar in perspective:

  • The studies showing that sugar consumption leads to obesity, diabetes, and heart disease have all been done with sodas and junk foods.
  • Many fruits have just as much sugar as a soda. They also contain about the same proportion of fructose and glucose as high fructose corn syrup. Yet we know fruits are good for us.
  • Diets rich in fruits, vegetables and whole grains decrease our risk of obesity, diabetes, and heart disease.
  • That is because the sugar in whole foods is generally present along with fiber and protein, which slows the absorption of sugar and prevents the blood sugar spikes we get with sodas and junk foods.
  • In the case of prepared foods like protein supplements, you should look for “low glycemic” on the label rather than sugar content. Low glycemic means that there is enough fiber and protein in the product to slow the absorption of sugar and prevent blood sugar spikes.
  • Don’t misunderstand me. I am not advocating for unlimited consumption of sugar. We should all work on ways to avoid sugar from junk foods or to reduce the amount of sugar in our diet. On the other hand, we don’t need to become so strict that we and our family need to eat foods that taste like cardboard. We also don’t want to replace natural sugars with artificial sweeteners.
  • We can go a long way towards reducing sugar by just eliminating sodas, other sugar sweetened beverages, junk foods, fast foods, convenience foods, and pastries from our diet. When considering fast foods and convenience foods, we should check the label for hidden sugar. When considering foods that are supposed to be healthy, we should look for the term “low glycemic” on the label.

For more details, read the article above.

 

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.