#214 Can Vitamins Make Up for a Bad Diet?

Can Vitamins Make Up for a Bad Diet?

Many people take a multivitamin as insurance for any nutrient that might be missing from their diet.  Could this thinking be flawed?  In this article, I share the latest research to answer the question, can vitamins make up for a bad diet?

The Latest Study

To answer the question, can vitamins make up for a bad diet? Harvard researchers dug through an average of 14 years worth of medical records from 13,316 male physicians.

Of course, one might ask if this is a fair study group.  After all, physicians are supposed to know a lot about nutrition and healthy diets, right?

While health knowledge certainly helps, physicians are no different than you.  Even though we know what we should eat, it is just as hard for us to resist temptations as well.

To see how tempted these male physicians were, researchers had them regularly fill out a 116 question survey of everything they ate for 14 years.  Based on the data from all these questionnaires, researchers could rank the quality of their diet and determine which vitamins and minerals they probably lacked.

Based on a “flip of the coin,” each physician was given either a multivitamin or a placebo.  As both the multivitamin and the placebo pills looked identical, the physicians in this study had no idea what they were taking.  Researchers then followed these physicians for 14 years to see who had a heart attack and who died.

Findings of the Physician Vitamin Study

Most people would naturally assume that for those eating a healthy diet, taking vitamins probably don’t help all that much.  To nobody’s surprise, this is exactly what this study determined.

Where things got interesting is whether or not vitamins can fix a bad diet.  Intuition would tell you that vitamins should help to correct a bad diet.  Surprisingly, these Harvard researchers found that even for physicians eating a crappy diet, vitamins didn’t prevent heart disease or an early death.

Fortunately, no harm was observed in this study from taking a multivitamin supplement.  I should also point out that in a separate publication from this study, these Harvard researchers saw a modest reduction in cancer risk from multivitamins.

What does this study tell us?

Probably the scariest finding of this study is that vitamins won’t make up for a bad diet.  In other words, taking a vitamin with your Big Mac and french fries won’t make your meal healthy.  And it certainly won’t prevent heart disease or an early death either.

You simply can’t expect a single isolated vitamin made in a chemistry lab to have the same effect as vitamins occurring naturally in healthy foods.  There are literally tens of thousands of compounds naturally occurring in fruits and vegetables.  Taking a manmade pill can’t replicate the interactions of these tens of thousands of naturally occurring compounds in food.

The real take away from this study is that to prevent heart disease and live a longer life, you really have to get all the vitamins and nutrients your body needs from food.  Shoot for 10 servings daily of vegetables and fruits.  Get at least one serving daily of nuts or seeds.  Try eating something high in the omega 3 fats everyday like walnuts, chia seeds, flax seeds, or fish.  Look for ways to get natural vitamin D in a sun smart way or by foods high in vitamin D like fish or mushrooms.  And do everything possible to avoid or minimize processed foods and sugars.

Even though this study didn’t show a benefit of vitamins in physicians eating a poor diet, I still recommend supplements for my patients with nutritional deficiencies that can’t be corrected naturally.  This is what I do for my own vitamin D deficiency that I can’t fix with sunlight and foods naturally high in vitamin D.

Can you really get all the vitamins you need from food?

For those people unsure of whether they can get all the vitamins they need from food, try an experiment. Download the free Healthwatch 360 app to your smartphone.  Then, track everything you eat for a week.

You will quickly see if you can get all the vitamins and minerals your body needs naturally from food.  For me, this experiment was a profound learning opportunity.  It gave me a much greater awareness of the nutritional quality of what I eat.  As I eat little to no dairy, I found that I had to dramatically increase my daily intake of salad, broccoli, kale, spinach, sesame seeds, and chia seeds to meet my daily calcium needs.

What is your take on vitamins?  Please leave your thoughts and questions below.  As always, I’ll try to answer every question within 24 hours.  To learn more, please be sure to subscribe to my free weekly newsletter and podcast.

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  1. I am 78 years old, I cannot eat 10 servings of fruits and vegetables. It is just too much food. In order to make sure I am getting enough vitamins and minerals, I grow organic vegetables especially Kale, Swiss chard, squash etc. I dehydrate these vegetables and make them into a powder. I add the powders to yogurt and tomato juice.
    By doing this I can get more vegetables in my diet. When the water is out, they do not fill me up so much.