Dieting = Nutrient Deficiencies?

Since I left home years ago, my dad routinely asks me if I’m eating healthy. Every time he’d call to see how I was doing, he’d tell me to make sure I made myself a glass of freshly squeezed orange juice every morning… until I told him you should avoid juice and eat the whole fruit. He now tells me to make sure I eat an orange every morning.

Is it that simple?

If I just follow my dad’s advice to eat an orange a day, do I cover all my nutritional bases?

Though I know my dad’s heart is in the right place and I find his advice endearing, it’s obvious that an orange a day — or even an apple — isn’t enough to meet all my nutritional needs.

But how do you know if you’re meeting your nutritional needs?

Nutrients: How much do you really need?

There’s a lot of talk of “eating healthy”. Your parents (like mine) probably ask if you’re “eating healthy”. Friends tell you, “That much protein isn’t healthy”, while eating a doughnut.

Usually all this talk of “eating healthy” is very vague and subjective. However, one way to measure, aka quantify, the “healthiness” of your diet is by examining its vitamin and mineral content.

The US government has figured out the rock-bottom amount of essential vitamins and minerals (micronutrients) needed for a healthy diet. They used to use recommended daily allowances (RDA); now they’ve moved to a new term: reference daily intake (RDI). RDI isn’t optimal; it’s just the baseline that you need in order to prevent malnutrition. That’s important to remember!

The American Dietetics Association recommends:

A few years back John wrote about a study that analyzed 70 people’s diets and there wasn’t a single person meeting all their nutritional requirements. Wow.

Obesity & nutrient deficiency

Since most obese people eat more food than lean people, you’d think that this extra food would give them more nutrients. Therefore obese people would have much fewer nutritional deficiencies but that’s not so. Overweight and obese people are over 80% more likely to have micronutrient deficiencies compared to lean people.

This week’s review looks at a study that may explain some of why overweight people are more likely to have micronutrient deficiencies.

Calton JB.  Prevalence of micronutrient deficiency in popular diet plans. J Int Soc Sports Nutr. 2010 Jun 10;7(1):24.

Methods

In this study the researcher looked at suggested diet plans from four well-known diets: the South Beach diet, the Atkins for Life diet, the Diet Approaches to Stop Hypertension (DASH) and the Best Life Diet.

He asked:

If you followed a given diet perfectly, what percentage of the RDI of 27 essential micronutrients would you get? Would you get all the vitamins and minerals you need?

• The South Beach Diet replaces “bad” fats and carbs (like trans fat and white bread) with “good” fats and carbs (like olive oil and whole grains). You could liken it to the Mediterranean diet.
• The Atkins for Life diet is a low-carbohydrate plan with a maximum of 20 grams of carbohydrates a day.
• DASH is a diet developed at the Mayo Clinic to reduce high blood pressure and limits sodium to about 3000 mg a day.
• The Best Life Diet comes from from Oprah’s trainer Bob Greene –  it’s a low-fat diet plan.

The researcher analyzed 15 meals from each diet to see how many essential micronutrients the plan contained, then calculated each diet plan’s content of these micronutrients using the US Department of Agriculture Nutrient Database for Standard Reference. The micronutrients included were:

Results

Let’s pretend that you haven’t read the title of the research article.

None of the four diets provided the RDI for all 27 micro-nutrients. Actually they barely meet the requirements for half the micro-nutrients.

In order of nutrient value:

1. The Best Life Diet has the most sufficient levels of micronutrient requirements. If you followed the Best Life diet perfectly, out of 27 micro-nutrients, you’d get 100% of 15 micronutrients. But you’d lack 12 micro-nutrients. Yup, this was the best diet of the four as far as getting your nutrients.
2. Second was the DASH diet, which provided sufficient levels for 14 of the 27 micro-nutrients.
3. Atkins offered 12 of the 27.
4. The South Beach Diet was way behind. It provided sufficient amounts of only 6 micronutrients. Six! If you include micro-nutrients that were over 90% RDI then you can get to 9 micro-nutrients.

Deficient nutrients

Across the board, all diets were miserably deficient in chromium. How bad was it? Eleven percent of RDI was the highest score, from the Best Life Diet. Bah, who needs chromium anyway? Well, if you’re trying to lose weight you might want some, since it helps with glucose and fat metabolism. Chromium isn’t particularly hard to find in food. It’s in broccoli, potatoes, whole grains, meat, apples, green beans, bananas, onions, tomatoes and lettuce.

Vitamin B7

Vitamin B7 (aka biotin) was the next most deficient nutrient with only the Body for Life diet reaching 90% RDI. The other diets were around 7-12%.  Vitamin B7 forms carboxylases (enzymes for glucose formation, leucine metabolism, making energy and making fat and for copying DNA). Again Vitamin B7 is found in a lot of foods. Green leafy vegetables, whole grains, salmon, avocado, lettuce, tomatoes, carrots, almonds, eggs, cabbage, onions, cucumber, cauliflower, berries, halibut, oat and walnuts are all sources of Vitamin B7.

Vitamin E

Vitamin E was also deficient in all the diets. DASH provided the most Vitamin E at 52% RDI. There are actually eight chemical family members that are covered under the name Vitamin E: four tocopherols, fat soluble alcohols with Vitamin E, and four tocotrienols. Alpha-tocopherol is what is mainly found in blood and tissues. Vitamin E works as an antioxidant, helps cells talk to each other, and helps immune cells work. Raw sunflower seeds, roasted almonds, olives, and spinach are good sources of Vitamin E.

Vitamin B5

Vitamin B5 (pantothenic acid) is in mushrooms, cauliflower, broccoli, seeds, greens, tomatoes, berries, eggs, yogurt, squash, corn, cod, split peas, lentils, avocado, sweet potato and whole grains. In this study the diet closest to getting 100% RDI was DASH (72%). Among other functions, Vitamin B5 is important for making cholesterol, steroid hormones and neurotransmitters.

Iodine

Iodine was also well below 100% RDI (around 34% on average), but since most salt is supplemented with iodine I doubt iodine deficiency occurs in real life in the Western world. In coastal areas around the world, people who eat seaweed also get iodine. Iodine is important for thyroid function.

Vitamin D

Another micronutrient that was deficient in the diets was Vitamin D, but since your body is designed to make Vitamin D when you’re exposed to the sun I don’t think this is an issue in the summer months.

How many calories would you need to hit 100% RDI in all micronutrients?

I guess for fun the researcher decided to see how many calories you would need to eat to get to 100% RDI for all micronutrients with each of the four diets.

Even though the Best Life Diet was sufficient in the most micronutrients you’d need to eat 20,500 calories to meet all your micronutrient requirements! You’d basically be eating between 5-10 times the calories you need to maintain your weight.

Atkins dieters need the most calories, 37,500, to reach micronutrient sufficiency and The South Beach needed the least, at 18,800 calories.

Conclusion

Popular diet plans, including medically reviewed (DASH), have some major micronutrient deficiencies with the biggest deficiencies happening in chromium, Vitamin B7, Vitamin E, Vitamin B5, iodine and Vitamin D.

Though the researcher recommends a multivitamin, you should take his advice with a grain of salt since he is the CEO of a company developing a multivitamin. (Although, don’t throw out the advice completely. A multi-vitamin is a good backup plan in certain situations).

My advice is either track your micronutrients with a nutritional program or consult with a professional to review your intake. By doing so, you’ll be able to focus on getting your micronutrients from whole food instead of a multivitamin, since there are many chemical compounds covered by one vitamin name, and since your body is better at absorbing nutrients from whole food.

Don't rely on these to meet your requirements.

Bottom line

Whether you’re eating to maintain or to lose weight, make sure you’re getting the micronutrients you need from whole food. Eating more brightly coloured fruits and vegetables will help you get the nutrients you need without many more calories.