The latest interesting study that I had the pleasure of running into deals with our liver and the damage that fast food has on it.

The study was done by Swedish scientists and was published back in February of 2008 in the GUT Journal (An International Journal of Gastroenterology and Hepatology). It is entitled “Fast-food-based hyper-alimentation can induce rapid and profound elevation of serum alanine aminotransferase in healthy subjects“.

In the past few days, this study is being written about in several online and hard copy publications as it has been brought to the attention of Dr. Brent Tetri of the Saint Louis University Liver Center. He is considered an expert on non-alcoholic fatty liver disease (NAFLD) and according to him the damage done to the liver can be reversed.

So as I said, floating around on the internet right now and probably in your local paper, are various versions of his take on this study and almost all the stories I found are simple copy-cats of each other. You can find one version of this story, perhaps the best one I could find, from Science Daily here. What I would like to do in this article is bring in for you a little different perspective in how you can use this knowledge to the best of your health and not get caught up in the usual one-sided media brainwashing.

The Original Study

The purpose of the study was to test liver enzymes and liver fat content in people who ate a typical fast food diet. There were 18 non-obese, healthy subjects used and made to eat at least 2 fast food meals a day for four weeks. There were also 18 parallel subjects used as the control group who did not eat the prescribed fast food diet.

The study found that after the four weeks, the fast food eating group: increased in weight, increased serum ALT levels (which is a liver enzyme that if found in the blood that can indicate liver damage/disease) and fats in the liver increased (i.e. a fatty liver leads to cirrhosis of the liver like in alcoholics).

The liver enzymes that indicate damage to the liver, rose as fast as in the first week on a fast food diet for some of the subjects but all eventually had high levels of the ALT enzyme. Insulin resistance also increased for the subjects by eating the fast food over the 4 week period.

They concluded that liver damage can occur on a fast food diet in less than four weeks and that NAFLD (Non-Alcoholic Fatty Liver Disease) and/or cirrhosis of the liver (which used to be an alcoholics disease) should now also be linked to high fat & high sugar diets.

These subjects also would have a smaller chance of survival if liver disease took over than per se an alcoholic in the same situation, as these subjects would also have heart disease. These higher than normal enzymes can also rise in any extreme unhealthy eating/drinking situations such as during holidays, not just in regular fast food eating. High ALT levels can also indicate future risk of Diabetes Type II. Ultimately NAFLD can be reversed with proper intervention.

Analysis of Study

In my opinion a study like this was long overdue and I am glad they did it. I am not fond of the fact that such a small subject number was used, but the scientists were still able to successfully get appropriate results.

The highlight of this study for me was also the fact that the scientists stress that doctors should be testing more patients for elevated ALT levels, regardless of alcohol consumption, as it can be a quicker indicator of possible serious, future health complications. The test is also easily done as a blood test so no liver biopsies necessary unless the results come back very poor. And if you are eating a diet high in fats and sugars, might not be a bad idea to ask your doctor for such a blood test.

So what’s the deal with your liver?

Our liver is the second largest organ in our body and one of the most critical organs next to your brain and heart. It has several functions that it serves in your body such as: detoxifying substances, lots of metabolic reactions, producing bile for fat break down and storing excess glucose. Hence I always stress, there should be no fooling around when it comes to your liver as liver disease and liver cancer have both increased greatly in the past few decades and very easily become life threatening. Having said that it always shocks me how loosely people take the consumption of alcohol and prescription medication, never mind eating high fat and high sugar diets.

I first became aware that fast food and just plain high fat and high sugar food causes liver damage after watching “Super Size Me“. (Great movie to watch – if you have never seen it!) And it appears that ever since that movie was made, more and more attention is brought forth to the idea of how much damage fast food actually does to the body, especially the liver. And thank goodness since most of the world today has been taken over by fast food mania.

Do you think it is a coincidence that McDonald’s, Wendy’s and most other popular fast food restaurants have started to include healthier choices on their menu in the past few years? Well, the answer is no. They knew that with such publicity, as the McDonald’s lawsuits and the release of the “Super Size Me” movie, more and more people began researching their food and so they had to do something not to lose all their customers.

The NAFLD Expert’s Opinion

Alright, so as I told you earlier, Dr. Brent Tetri, a US liver expert has come forth and given his take on this study. He rightfully agrees that a diet high in fast food can be toxic to the liver by causing significant damage to your liver and also pose other serious consequences to your health.

Dr. Tetri also explained that we are seeing cirrhosis of the liver in kids and teenagers today, where once this was only seen in alcoholic adults. He also stresses that it is not the fast food per se that causes liver damage but the high amounts of calories, fats and sugars.

However, what else Dr. Tetri said is that the good news is, is that most people can undo this damage mainly by altering the diet and exercising. He gives the following four steps to reversing the damage caused by the liver:

  1. Limit yourself to no more than one fast-food meal a week. For some people, that’s going to be a major downshift. But for the sake of your health, a visit to a fast-food restaurant should be considered a treat – not a regular event.

  2. When you do eat fast food, eat as healthfully as possible. Try the burger without mayo and cheese, and avoid fries and sugary soft drinks. Better yet, go for a grilled chicken sandwich, a salad with a lower-fat dressing and bottled water or a diet soft drink.

  3. Get active. If you don’t already exercise at least three times a week, start now. Regular exercise helps keep your weight down and helps your body better metabolize and process the food you eat.

  4. Ask your doctor to do a blood test to check your level of liver enzymes, a key measure of the health of your liver. Many doctors now order this test routinely when doing blood work on adults, but kids who eat a lot of fast food especially need to have their liver enzymes checked.

Analysis of Dr. Tetri’s Stand

For the most part I strongly agree with most of what Dr. Tetri has to say. Yes the typical American Fast Food Based diet is a killer to your health! And hopefully, you are not making fast food part of your daily meals. Again if you want the quick and fun way of seeing what can happen – just watch Super Size me.

Now the only remark I have to make in regards to what Dr. Tetri has said and what the stories that talk about these studies are saying is that they are making it way to passive! Liver damage is serious and I feel some people, especially teenagers are going to reason it out this way: “well, since it is reversible then I’ll just enjoy the fast food now and get serious about it later”.

This is where I strongly disagree with some of the content in Dr. Tetri’s 4 steps to reversing liver damage.

Step 1:

He says to limit yourself to one meal a week of fast food – how about none?! Why is it so hard for a doctor to step up to the plate and simply acknowledge that fast food should be avoided? You tell people they can have one meal a week, you will get people reasoning it out as “well, if I can have 1, I am sure 2 won’t hurt me…” and so on.

Then, also in step 1 he finishes off by saying that “a visit to a fast food restaurant should be considered a treat”. Now I do not get this, how is hurting your body a treat? This issue sits huge with me as I have realized that our society has completely misused the term “treat”. Soda, cakes, fast food are not treats! How is it a treat to give your body junk? I know he is trying to reach the mainstream public and go easy, but until someone will take a firm stand and admit we should not be consuming some substances in any amounts, I am afraid we may not get very far when it comes to improving people’s health.

Step 2:

In this step Dr. Tetri says that when you do go, eat as healthfully as possible. Unfortunately these days one can no longer say that the chicken sandwich is healthier than a burger, or a salad is healthier than a chicken sandwich. In reality, if it comes from a fast food restaurant, none of those choices are optimally healthy. And as always, as I share through my work, we CANNOT, absolutely CANNOT use the excuse “but I do not have time for other food”, IF we are serious about our health.

The worst part about step 2 is that he recommends diet soda!!!! As if soda wasn’t bad enough already, now you are telling people to drink the stuff with the neurotoxic aspartame? I understand that he is trying to prevent liver damage but at what cost getting brain tumors? And actually aspartame has been linked to liver cancer too.

Step 3:

Nothing wrong with this point as long as people do not misinterpret and/or think that exercising undoes the negative effects of cholesterol and chemicals in your system. Yes it will help you burn the fat and keep excess weight off, but it won’t undo all the damage of the meal. A big myth people have is that thin people do not suffer from high blood pressure, high cholesterol or heart disease and hence are healthy. Some very thin people can actually have very unhealthy cardiovascular systems, liver disease, etc.

Hence, eating burgers and fries is not cancelled out by miles of jogging. You may keep the weight off, but your insides will still suffer damage.

Step 4:

Excellent advice in this point! It is very wise for anyone who has or had a sketchy diet filled with fast food, or high fat, or high sugar to have their liver enzymes checked. Maybe the results will be your tipping point for leaving sodas, burgers and other fast food favorites behind once and for all.


So in conclusion, I am glad that the Swedish study is getting so much attention. My only purpose for this article is to give you a better explanation of how you should go about applying these results in a practical and optimally healthy way, not getting a false sense of security due to some of Dr. Tetri’s comments.

Personally, I do not think there is a safe level of fast food one can eat and not suffer some damage. Equally so, nothing really from any of these places can be called “healthy”. McDonald’s for example even made a simple bowl of oatmeal, an unhealthy option. This is why I wish people in influential positions, such as doctors were braver to bring that message forth, and not be passive about it, afraid of offending anyone, catering to the billion dollar fast food industries that are destroying people’s health.

Fast food is bad for your health period. Plus, it is not cost effective if you compare home cooking of non-processed items. And if you are still finding yourself in the boat called “no time”, you don’t have to wait for New Year’s resolutions to rearrange your life based on valuable priorities such as your health. Remember all it takes is a bit of conscious living and will power to make anything happen – but as always the choice is yours!