If you eat a balanced, whole-food diet like the one described in my nutrition plan, you’re probably getting adequate amounts of the vitamins and minerals your body needs to function.

If not (and this applies to the majority of the U.S. population), there’s a good chance you may be lacking important nutrients.

Even if you do eat well, how and where your food was grown can also influence your nutritional intake. Soil quality, storage time, and processing can significantly influence the levels of certain nutrients in your food.

Your age and certain health conditions (digestive issues and others) can also impact your body’s ability to absorb the nutrients in your food.

Unfortunately, in many cases nutrient deficiencies can be difficult to assess, and you may not develop symptoms until the deficiency has become quite pronounced.

Below, I will review 11 of the most common nutrient deficiencies,¹ and how to address them. Eating real food is usually your best bet, but sometimes supplementation may be advisable, especially if you’re showing signs of deficiency.

#1: Vitamin D

Vitamin D deficiency is prevalent in people of all ages, especially in those who choose to use topical sun screens (which blocks vitamin D production) or limit their outdoor activities.

Researchers estimate that 50 percent of the general population is at risk of vitamin D deficiency and insufficiency, and this percentage rises in higher-risk populations such as the elderly and those with darker skin.

Signs indicating you may have a vitamin D deficiency include being over the age of 50, having darker skin, obesity, achy bones, feeling blue, head sweating, and poor immune function.   

Your best bet is to get your vitamin D level tested twice a year. Based on the evaluation of healthy populations that get plenty of natural sun exposure, the optimal range for general health appears to be somewhere between 50 and 70 ng/ml.

As for how to optimize your vitamin D levels, I firmly believe that sensible sun exposure is the best way, although vitamin D-rich foods and D3 supplements may also be necessary if you cannot get adequate sun exposure year-round.

How to Optimize Your Vitamin D

To optimize your levels, you need to expose large portions of your skin, such as your back, chest, legs, and arms, to sensible sun exposure. And, contrary to popular belief, the best time to be in the sun for vitamin D production is actually as near to solar noon as possible.

During this time you need the shortest exposure time to produce vitamin D because UVB rays are most intense at this time. Plus, when the sun goes down toward the horizon, the UVB is filtered out much more than the dangerous UVA.

Just be cautious about the length of your exposure. You only need enough exposure to have your skin turn the lightest shade darker. Once you reach this point your body will not make any additional vitamin D due to its self-regulating mechanism. Any additional exposure will only cause harm and damage to your skin.

Avoiding processed foods is another important consideration, as they tend to be loaded with the herbicide glyphosate (used on most conventional and genetically engineered food crops), and glyphosate has been shown to interfere with enzymes responsible for activating vitamin D in your liver and kidneys.  

#2: Omega-3 Fats

Low concentrations of the omega-3 fats EPA and DHA² are associated with an increased risk of death from all causes, and omega-3 deficiency has been revealed as the sixth biggest killer of Americans.

Most Americans eat too many inflammatory omega-6 fats (think processed vegetable oils) and too few anti-inflammatory omega-3s, which sets the stage for a number of health problems, including cardiovascular disease, cancer, depression, Alzheimer’s, rheumatoid arthritis, and diabetes, just to name a few.

Telltale signs that your omega-3 to omega-6 ratio may be out of balance include dry, flaky skin, alligator skin, or “chicken skin” on backs of arms; dandruff or dry hair; soft brittle nails; fatigue; menstrual cramps, and poor attention span.

The ideal ratio of omega-3 to omega-6 fats is about 1:1, but the typical Western diet is between 1:20 and 1:50, so in addition to upping your omega-3 intake, you also need to reduce the amount of omega-6 in your diet, which means cutting down on processed and fried foods.

Sardines are one of the most concentrated sources of omega-3 fats,³ with one serving containing more than 50 percent of your recommended daily value. They also contain other nutrients that many are deficient in, such as vitamin B12, calcium, and choline.

If you decide to take omega-3s in supplement form, I believe krill oil is superior to fish oil. The omega-3 in krill is attached to phospholipids that increase its absorption, which means you need less of it.

Krill oil also contains almost 50 times more astaxanthin, a potent antioxidant, than fish oil, which prevents the highly perishable omega-3 fats from oxidizing before you are able to integrate them into your cellular tissue.