Whether you follow a diet that doesn’t give you all the vitamins you need or you’d like to maintain optimum health, supplements are a great way to ensure your body gets everything it needs. The only problem with supplements is that I see all too many of my clients coming to see me with bags full of the different supplements they take each day, all of which promise to do a different thing. The problem here is that many of these supplements contain the same things.

It’s essential to get the right dosage of micronutrients. It’s tempting to take as much as possible, but some can cause side effects when taken in excess, and others will just be flushed out of your system. Conversely, some vitamins are actually better when taken at higher doses – so, how do you figure it all out without an MD?

Read on and I’ll guide you through everything you need to know!

 

What is a fat-soluble vitamin, and what is a water-soluble vitamin?

Before you can figure out the right doses, you need to understand the difference between a fat-soluble vitamin and a water-soluble vitamin.

A fat-soluble vitamin means that it needs fat to be taken up by the body. For this reason, these vitamins are best taken with food.

A water-soluble vitamin means that it needs water to be taken up by the body.

 

Can you ingest too many fat-soluble vitamins?  

Fat-soluble vitamins are the only vitamins you need to really think about trying get just enough about, and not too much. The fat-soluble vitamins are: A, D, E, and K.

It’s all too easy to take too many fat-soluble vitamins, especially if you’re taking multiple supplements. In high doses, these vitamins can even cause toxicity, so it’s important to be aware that you really can get too much of a good thing. You need to find a single supplement that offers you a suitable dose of all of these, or carefully select your different supplements so you don’t take too much.

Generally, it is considered unsafe to take more than:

Vitamin A: 1.5mg

Vitamin D: 4mg

Vitamin E: 1,000mg (though 15mg is more appropriate)  

Vitamin K: there is no upper intake level set, though around 90mg for women is the recommended intake, so it’s best to stick close to that number

It’s also important to note that these numbers can differ significantly if you are pregnant or on medication, so speak to your doctor about the right dosage for you and what is safe and recommended to take.

 

Why is it safe to have a high amount of water‐soluble vitamins and not fat-soluble vitamins?

If you ingest too much of a water‐soluble vitamin, you will most likely just urinate it out. And the benefit of having a mega dose of a water‐soluble vitamin is that when we take a vitamin orally, it has to go through the gut. Considering our (generally) poor gut health, we could probably do with something to give our guts a helping hand. In other words, you want a higher water-soluble vitamin dose to compensate for the fact that you're probably only going to absorb a percentage of the vitamin you take. 

 

How much of my daily vitamin will I actually absorb? 

The number of vitamins absorbed depends on the individual. The worse a person’s gut health, the less they will absorb. If someone eats a balanced diet and lives a healthy lifestyle with no gut issues, they’ll take up what they need and urinate out the rest, and so won’t need a high dose.

Those with poor gut health need to compensate for the fact that they have a more difficult time taking up vitamins with a larger dose, but you're not harming your body by taking a higher dose because you'll just urinate anything you don’t use out.

 

What should I do if I have gut issues and want to make the most of my vitamins? 

If someone does have poor gut health, they will need more micronutrients because they're less likely to absorb the micronutrients through the food they eat. We live in a society where most people have poor or compromised gut health. So, you give a higher dose of the safer water‐soluble vitamins to compensate for the deficiencies that have developed due to the compromised gut health. So, for example, if someone with poor gut health has a salad, they're only absorbing a small percentage of the vitamins and minerals and nutrients in that salad when compared to someone healthier, so they're more likely to have vitamin deficiencies. 

 

What should I do if I’m deficient in a certain vitamin and have poor gut health? 

If you’re short on a vitamin, you will need a larger dose to compensate for the deficiency. For those with a deficiency, the likelihood of the vitamin being absorbed by the cell and becoming effective depends on the concentration of vitamins that are ingested.

You want to give a high dose of a water‐soluble vitamin so that it blasts the cells with these vitamins to ensure intake by the cells. That’s the only way the vitamin can be effective in the body. The more you have of the water‐soluble vitamin, the higher the concentration in your blood. With a higher concentration of the vitamin, you’ll have a better chance of absorbing enough of the vitamin. 

 

How do these vitamin doses compare to a traditional Meyer’s cocktail? 

The Myers cocktail is an IV that was developed by Dr. John Myers in the 1960s, which is a bag of high dose vitamin C, B vitamins, calcium, magnesium. It contains a minimum of 5,000 milligrams of vitamin C. The popularity or the efficacy of this drip came from the fact that it’s directly absorbed into the bloodstream. You are bypassing the gut by infusing these high-dose, water-soluble vitamins into the vein. Poor gut health doesn't interfere with the efficacy of an IV that goes directly into the bloodstream, so it worked well for those with gut issues. 

The Myers cocktail contains mega doses of these water‐soluble vitamins because the higher concentration of these vitamins in the blood is much more likely to be incorporated by the cells. You can take these high doses of water-soluble vitamins safely orally or via IV therapy.

 

In Summary: Choosing the Right Supplements

Be conscious of what’s in your supplements, and don’t simply look at the marketing on the label. The truth is, most vitamins and minerals have multiple uses in the body, so three different supplements may all contain the same vitamin – however, this is only an issue when it comes to taking too many fat-soluble vitamins. If you believe your gut health is poor, try taking probiotics to give your gut that much-needed boost.

 

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Dr. Nancy Rahnama, MD, ABOM, ABIM, is a medical doctor board certified by both the American Board of Obesity Medicine and the American Board of Internal Medicine. Her specialty is Clinical Nutrition, that is, the use of nutrition by a medical doctor to diagnose and treat disease. Dr. Rahnama has helped thousands of people achieve their goals of weight loss, gut health, improved mood and sleep, and managing chronic disease.