Did I get you with my title? Perhaps you imagined that you would learn in these pages about what was truly good for you, nutritionally speaking. Did you wonder if it was possible that someone might have the truth? My apologies, but I do not. My title was merely a hook, an age-old method of getting the reader interested, willing to slog through assorted facts presented, hoping to find some straight talk about nutrition.

I do have an abundance of facts about this complex topic, which I hope to impart, but there is so much I can’t tell you. That is because much disagreement exists about diet and health. As a famous tv show once proclaimed “the truth is out there,” but we do not yet know it.

It is commonplace for an average Joe to state, when this topic is brought up, “Who knows!” and he or she would be right. It would seem almost daily that a new theory is proposed, or some study points to ‘the truth’ about what to eat, and what not to. We have learned much over the last few decades, but the number of conflicting opinions on the part of scholars and experts leads one to believe we haven’t yet gotten there.

A perfect example would be the effects of the ingestion of fat on a human’s health. Many still cling to the belief that fats are bad. This, despite the fact that we need fat in our diet to survive.

Fats are composed of various a group of substances called lipids, and these substances make up an essential part of the cell wall of every cell in our body.

The AMA proposed the food pyramid (foisted upon western culture back in the 1950’s) to be the gospel, in which starches, aka carbohydrates, were the foundation of a healthy diet. The damage wrought by this recommendation is incalculable.

The human body needs fat to survive! Dietary fats are essential to give your body energy and to support cell growth. They also help protect your organs and help keep your body warm. Fats help your body absorb some nutrients and produce important hormones, too. Your body definitely needs fat. Then why was such a grandiose directive made? The food pyramid, as fashioned in the 1960’s, stated that we should consume, as the basis of your dietary intake, starches, and work to reduce the consumption of fats. But what is starch? Sugar! Certainly, some starches break down in our bodies faster than others, but still, as a class, they are of poor nutrient value.

What are the facts? We know there are four major categories of dietary fats, each with their own structure and properties. Saturated fats are generally from animal sources, and have been blamed for everything from heart disease to an increased risk of stroke. These tend to take a solid form at room temperature, like a stick of butter.

Trans fats are a separate but equally vilified category, created in an industrial process (like a good motor oil?), whereby vegetable oils are altered to make them more solid. They are utilized in the production of most processed foods. Unfortunately, there is no clear evidence as to how the human body handles these substances, which are a manufactured product and do not occur in nature.

Unsaturated fats are those found in certain food sources, with prime examples being fish (especially salmon, herring and trout), avocados, olives, walnuts, as well as vegetable oils such as soybean, safflower, canola, olive and sunflower oil. If cholesterol levels are the most important factor in determining what foods are healthy (and that has become a controversial concept), these foods appear to help lower your blood levels.

But is that the most important thing?

The role of blood cholesterol levels in heart disease and the true effect of cholesterol-lowering statin drugs (obviously supported by the massive pharmaceutical industry), remains debatable. In particular, do statins actually increase life expectancy? Early statin trials reported significant benefits to health and mortality, yet serious concerns have been raised in some studies regarding biased results, premature trial terminations, under-reporting of adverse events, high numbers of patients lost to follow-up, and oversight by the pharmaceutical company sponsor.

A major, large-scale clinical trial was performed decades ago which looked at diet and the effect of meals rich in saturated versus unsaturated fats. This study, conducted at state mental hospitals, was funded by the National Heart, Lung and Blood Institute. The study was intended to show that removing saturated fat from people’s diets and replacing it with polyunsaturated fat from vegetable oils would protect them against heart disease and lower their mortality.

Unfortunately, the data was never fully analyzed, despite being one of the largest controlled clinical dietary trials of its kind ever conducted. While it is unclear why the trial data had not previously been fully analyzed, the results were a surprise. Participants who ate a diet low in saturated fat and enriched with corn oil reduced their cholesterol by an average of 14 percent, compared with a change of just 1 percent in the control group. But the low-saturated fat diet did not reduce mortality. In fact, the study found that the greater the drop in cholesterol, the higher the risk of death during the trial. The findings run counter to conventional dietary recommendations that advise a diet low in saturated fat to decrease heart risk.

Recent studies have looked at mortality rates from a more objective perspective, rather than effects on cholesterol. Does an individual’s cholesterol levels matter? That remains in question, despite the fact that these expensive drugs, having known complications with use, are prescribed by practitioners on a daily basis. That is the action recommended by the major health institutions. Physicians have simply been following prescribed practices. Yet coronary heart disease remains at pandemic proportions.

Perhaps there are problems with making specific recommendations, affecting the treatment of the general public, based on studies that are biased, or flawed. The food pyramid was developed on the basis of two very flawed studies. The obesity epidemic can be traced, in some respects, to the creation and propagation of the food pyramid. Is it appropriate, is it wise, to incur the expense, the possible problems and complications, for major medical institutions to demand doctors prescribe these drugs, prior to recommending lifestyle changes.

I doubt anyone would say that this latter option is easy. Currently, the Mediterranean diet model has been shown to prolong life and reduce the risk of diabetes, cancer, and heart disease. So has regular exercise, which is another very difficult change to make in one’s life.

But, when done intelligently, following a healthy diet (such as the Mediterranean diet), and getting appropriate exercise is known to reduce the risk of heart disease, cancer, diabetes, and a variety of chronic diseases, and do it safely. Doesn’t it just make sense to try these changes, as opposed to introducing a manufactured drug, some foreign substance, when we know a certain percentage of people are going to have problems with it?

What is the truth, when it comes to the question of what kind of diet will lead to your greatest chance of a healthy life? Clearly, eating whole, unprocessed foods, plant-based, seems to be the way to go, with the Mediterranean diet being the best studied example (which reduces mortality within months of initiation, even if scientists are unable to explain how). The truth about nutrition and health is out there, but we clearly don’t yet know what it is.

Editor’s note: Dr. Conway McLean is a podiatric physician now practicing foot and ankle medicine in the Upper Peninsula, having assumed the practice of Dr. Ken Tabor. McLean has lectured internationally on surgery and wound care, and is board certified in both, with a sub-specialty in foot orthotic therapy. Dr. McLean welcomes questions, comments and suggestions at drcmclean@penmed.com.