The vitamin and supplement industry turns over billions of dollars each year. Some are claimed to alleviate minor symptoms like achy joints, others are promoted as life-extenders or cancer curers.

Even sensible people who want to avoid basic deficients often take multivitamins. The problems with multivitamins, however, are fourfold:

  1. Foods are already fortified with vitamins. Taking a multivitamin could lead to overdose.
  2. Not everything you may need can be contained in a convenient one-per-day pill.
  3. Not all healthy compounds are actually vitamins and wouldn’t be found in a multivitamin.
  4. The recommended daily intake is often the minimal daily intake. We may need more for optimal health.

Multivitamins, on top of their inherent flaws are also pretty useless. Studies show that they’re neither helpful or harmful. They’re a waste of money.

That said, just because multivitamins are useless, that doesn’t mean vitamins in general are. Some of us are deficient in particular vitamins and can suffer poor health as a consequence.

Below I’ll list the most common vitamin deficiencies you might be suffering and show you how you can overcome these and attain optimal health today.

Vitamin D

Vitamin D, also known as the sunlight vitamin, is primarily manufactured body out bodies in response to sun exposure. Because of the dangers of sun and the nature of our clothing vitamin D is incredibly difficult to get in optimal dosages. In fact, it’s the most widespread vitamin deficiency in the developed world.

When optimal levels of vitamin D are met, everything from dementia to fracture risk to mood is improved. It even halves the chances of getting colorectal cancer and is vital for proper calcium absorption.

The recommended daily intake for vitamin D falls between 400-800 IU. The optimal range for most people, however, is between 1,000-5,000IU.

How to take vitamin D

Simply take one capsule a day, 2,000IU is a good place to start. Take it with some fat.

Vitamin K

Most of us aren’t deficient in vitamin K, but that doesn’t mean we have enough of it. The RDI of vitamin K is 50mcg. Optimal levels are 20 times this amount. Again, it’s almost impossible to get this from your diet unless you eat bags and bags of steamed and blended kale everyday.

Vitamin K regulates healthy blood clotting, thickens your bones and amongst many other benefits, keeps you skin strong and firm.

How to take Vitamin K

Aim to get 1000mcg of vitamin K1 everyday. Take it with some fat for maximum absorption.


The rest of the compounds discussed are not vitamins, but minerals. They’re usually contained in multivitamins, however, and carry out vital tasks in the human body.

Calcium deficiencies are widespread in the elderly, especially when vegetarian or low dairy diets are combined. If you drink milk, and dairy on a regular basis you probably won’t be deficient in this mineral.

Calcium deficiencies make your bones and teeth more fragile. Which can then lead to other complications such as tooth infections, or bone fractures.

How to take calcium

Take 500-750mg of calcium everyday with some food.


Iron deficiencies are most common in pregnant women, non-meat eaters and regular blood donors. Because excess iron can be toxic, great care needs to be taken upon supplementation.

Iron deficiencies can cause hair loss, pale and fragile skin, hyperthyroidism and dizziness.

How to take iron

If you suspect yourself deficient in iron, seek the advice of a medical doctor. They can take your blood and give you a suitable dosage to bring your iron levels back to normal.


Magnesium is the second most common vitamin deficiency in the developed world. Proper magnesium levels help with blood pressure, insulin sensitive, bone mineral density, sleep quality and lots more.

If you eat nuts on a regular basis you probably won’t be deficient in iron. If you don’t then perhaps a supplement is nessesary.

If you eat a lot of nuts then you probably don’t need to worry about being deficient in magnesium. If you don’t eat many nuts and you don’t want to start (they have lots of calories), then you can supplement 200-400mg each day with a meal.

How to take magnesium

Take 200-400mg each day with a meal or on an empty stomach. You can buy ZMA which combines zinc with magnesium if you happen to need both.


Zinc deficiencies are linked to hair loss, bad skin, depression and low testosterone. Optimal levels improve blood glucose and insulin sensitivity.

Zinc deficiencies are most common in those who are active and don’t eat meat — in particular, beef.

How to take zinc

Aim to take 30mg of zinc gluconate every day — with or without food.

If you eat a healthy and varied diet, like the type promoted by Health Today then you probably won’t be deficient in many – if any – vitamins and minerals. However, as the article explains getting optimal levels of a particular vitamin is a completely different problem. Most people will need to supplement with vitamin D and vitamin K for optimum health. As for the minerals, that is context-dependent.