How to Optimize Your Nutrient Intake—Varied Diets Are Key

From a Lecture Series Presented by Professor Roberta H. Anding, M.S.

Food companies often boast that their products are high in fiber or certain vitamins and minerals. Studies show that variety is key in a diet, so which foods should we focus on to get our recommended daily allowance of nutrients?

Image of fresh fruits and vegetables

There are only minor differences in nutritional quality of food depending on the production methods. Meanwhile, in modern times—and for the first time in human history due to globalization, for example—we have access to a variety of fresh fruits and vegetables year round. It’s important to take advantage of that. Year round, you can get tomatoes, strawberries, and bananas—a variety of fruits and vegetables that will have a much greater impact on your overall nutrition than the mild differences between different food production methods.


Vitamins are only part of the nutritional content of the food that we need to be concerned with. They are part of what we call the micronutrients. Let’s turn now to the macronutrients. Macronutrients are those parts of food from which we get calories or energy and also structural components, the stuff that we actually build our bodies out of. There are some essential fatty acids and amino acids, but these are not technically vitamins because we need them in more than tiny amounts so they’re still considered part of the macronutrients.

Let’s discuss the three main types of macronutrients that we get in our diet. These include carbohydrates. Carbohydrates are sugars and also starches like bread or pasta. There’s also lipids. Lipids are, essentially, fats and oils. There’s also protein. Protein comes from meats as well as nuts and legumes.

You should definitely avoid highly restrictive or narrow diets that are dependent on just a few different kinds of food. Click To Tweet


Food also contains, in addition to vitamins and the macronutrients, many minerals or “trace minerals” as they’re often called. These include calcium, phosphorus, magnesium, iron, zinc, copper, sodium, and potassium. These are also sometimes referred to as electrolytes. Electrolytes are simply minerals that exist in our bodies in their ionic form. For example, sodium with a positive charge is the electrolyte sodium. But, it is still considered a mineral that we get from our food.

Incidentally, you can overdose on minerals as you can on many of the vitamins. The most common mineral overdose is iron. In fact, this is the most common childhood overdose of all. This is because children will often get iron from vitamins which they may think of as candy, not necessarily medicine. Adult males do not need to supplement iron at all. In fact, they recycle almost all of their iron. Therefore, the only people who really need to supplement are those who are anemic or women who are menstruating because they need to replace the iron they lose each month.

Where to Find Vitamins in Food

Let’s talk a bit about optimal nutrition. How do we get all the things that I spoke about in our food? There is general agreement in the scientific community that the best way to get good nutrition is through a well-balanced, varied diet. Variety is the key. You should definitely avoid highly restrictive or narrow diets that are dependent on just a few different kinds of food. The USDA food pyramid goes over the rough proportions of different kinds of foods that would be contained in a healthful diet.

This is a transcript from the video series Nutrition Made Clear. It’s available for audio and video download here.

Here’s a basic overview. A healthful diet should contain and should emphasize these things: about 2 cups of fruit and 2-1/2 cups of vegetables per day. You don’t have to measure these out precisely. This is really just a rule of thumb, a guideline to help you estimate that you’re getting enough of the different kinds of food you should be eating. When you do eat vegetables, you should try to pick from the different subgroups of vegetables. These include dark green vegetables, orange vegetables, legumes, starchy vegetables, and other vegetables.

In addition, you should get three or more ounce-equivalents of whole grain products per day with the rest of your carbohydrates coming from either enriched or whole grain products. You should also have three cups per day of fat-free or low-fat milk or equivalent milk products. Of course, to round out your diet, you’re also going to be getting protein from lean meats as well as eggs, nuts, and legumes.


What about superfoods? Are there some foods that are so nutritious that we can get really great nutrition just from eating a small amount of them? The bottom line is that there is no food in a pill and there is no food that you can take in tiny amounts that will have a significant impact on your overall nutrition. Examples of some kinds of foods that are marketed as so-called superfoods include spirulina. This is essentially pond algae. There’s also wheatgrass juice, which I’ve actually tried and I don’t recommend it. It’s not very tasty. The notion is that it contains special nutrients like chlorophyll and high doses of vitamins that can act as a superfood. In reality, it has no more vitamins or nutritional content than common fruits and vegetables that are much tastier.


Tropical superjuice, like açaí juice, claim to have all kinds of vitamins and nutrients. But, when you look at the data, it’s just another kind of fruit juice.

There’s also the latest fad tropical superjuice, like açaí juice, for example. It’s claimed to have all kinds of vitamins and nutrients. But, again, when you actually look at the data, it’s just another kind of fruit juice. What about natural vitamins? If you do supplement for whatever reason, should you look for natural vitamins instead of synthetic vitamins based on the notion that they will be more effective or that they will have more of a healthful effect?

It turns out that ascorbic acid is ascorbic acid, for example. If you have synthetic vitamin C versus vitamin C that is derived from say a plant source, the chemical structure is identical. Therefore, the chemical properties are identical as well. The source doesn’t matter to the chemical properties of that molecule.

Soil Depletion

Image of crops in a dry field One topic that comes up frequently among those who are concerned about the nutritional quality of our food is soil depletion. There are reports that perhaps due to modern agriculture, we are depleting our soil of the minerals that are necessary. Therefore, we’re losing those trace minerals from our diet. Most people who make this point or who are concerned about this will refer to a 1936 Congressional statement. It turns out that, when you look at it closely, this was an article that was written in Cosmopolitan magazine, a literary magazine. This was inserted into the Congressional Record by Senator Duncan Fletcher from Florida. But, that becomes a primary reference for those who argue that our soil is depleted. They say, hey if it was that depleted in 1936, imagine how bad it must be today.

Reports that our soils are depleted of minerals are often misinterpreted. It turns out that soil is actually frequently tested for its mineral content. Minerals are added in the farming process, in the fertilization process of the soil. The plants need the minerals to grow as well. Agricultural companies want to replete those minerals so that their yields will be maximal. That mineral content is in the food.

Frozen food is definitely better than canned in terms of its nutritional content. Click To Tweet

Fresh vs Frozen and More

Which different types of food are most nutritious depends on how it’s prepared and packaged. It is true that cooking decreases the nutrient content of food—not too much, but it is measurable. It does decrease the nutritious content. It is important to eat fresh fruits and vegetables to get maximal nutrition—or just lightly steam them. You should avoid thoroughly boiling food because that does leach out much of the vitamins and minerals.

What about frozen versus fresh and canned? Frozen food is definitely better than canned in terms of its nutritional content. In fact, frozen vegetables may be slightly better than fresh if they are picked at the peak of ripeness and frozen at that time—versus vegetables which are allowed to ripen in transport or in the stores, for example.

What about organic food? The reviews of published evidence showing that there are only negligible differences in the nutritional quality between organic and non-organically grown food.

Keep reading:
The ABCs of Vitamins
A Plateful of Vitamins: Foods That Fulfill Your RDA

From the Lecture Series: Nutrition Made Clear
Taught by Professor Roberta H. Anding M.S.