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What You Need To Know About Water-Soluble & Fat-Soluble Vitamins

William Cole, IFMCP, DNM, D.C.
April 19, 2018
William Cole, IFMCP, DNM, D.C.
Functional Medicine Practitioner
By William Cole, IFMCP, DNM, D.C.
Functional Medicine Practitioner
Will Cole, IFMCP, DNM, D.C., is a leading functional medicine practitioner with a certification in natural medicine and a doctor of chiropractic degree.
Photo by Michelle Patrick Photography LLC
April 19, 2018

By the time my patients come to see me at my functional medicine center, they're typically well-versed in health and wellness and know quite a bit about supplements, lab testing, and the ins and outs of healthy living. They've been consulting Dr. Google and other resources for a while, and they eat better than the majority. But despite their best efforts, they are still struggling with health issues. My job is to take their wellness journey to the next level, optimize their current plan, and find out what is missing from their health puzzle.

Another variable I have to manage is their "supplement graveyard." You know, that cabinet filled with all the vitamins, powders, and potions that just grows and grows. You take one for a few weeks and move on to the next, never really knowing why you chose them or what they do. An important thing to know about your supplements is the difference between water-soluble or fat-soluble vitamins, so let's begin there:

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The water soluble-vitamins

Water-soluble vitamins are naturally found in the—you guessed it—water that resides in different foods. Unlike their fat-soluble cousins, water-soluble vitamins aren't normally stored in the body. If they're not gobbled up by the body, they're simply excreted in the urine. This means that water-soluble toxicity is uncommon, and it also means that we need to make sure to get them regularly from the foods we eat and supplementation, if necessary.

1. B vitamins

This family of vitamins consists of eight different compounds that have similar health benefits and functions and are often found in the same foods. Meet the vitamins in the B-complex family:

  • B1 (Thiamine)
  • B2 (Riboflavin)
  • B3 (Niacin)
  • B5 (Pantothenic acid)
  • B6 (Pyridoxine)
  • B7 (Biotin)
  • B9 (Folate)
  • B12 (Cobalamin)
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In addition to getting B vitamins from our foods, some Bs can also be made by our healthy gut bacteria! B2, B5, B6, B7, B9, and B12 can all be made by the microbiome. As if you needed another reason to support a healthy gut! Here's why you need B vitamins:

Luckily, quite a few foods naturally contain B vitamins, including:

  • Meat (organ meats like liver are the highest sources; red meat is the second richest)
  • Nuts
  • Avocados
  • Egg yolks
  • Seafood (fatty fish like salmon and mackerel as well as shellfish)
  • Seeds
  • Green leafy vegetables (like spinach)
  • Sulfur-rich vegetables (like cabbage)
  • Yogurt
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2. Vitamin C (ascorbic acid)

Vitamin C is probably the most well-known supplement, likely because many people start upping their daily intake when they start feeling sick. Here's why vitamin C is so important:

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You can supplement with vitamin C, but there are a ton of foods that also contain a bunch of this healthy nutrient:

  • Citrus fruits (oranges, lemons, limes, and grapefruit)
  • Broccoli
  • Peppers
  • Leafy green vegetables
  • Strawberries
  • Kiwifruit
  • Papayas
  • Cantaloupes
  • Organ meats

The fat-soluble vitamins

Fat-soluble vitamins are dissolved in fat and need to be paired with healthy fats to be bioavailable. The modern Western diet, which has long feared fatty foods, is dreadfully deficient in fat-soluble vitamins. These vitamins are immensely important for hormone, brain, and immune health. Unlike water-soluble vitamins—which are cleared out in water—fat-soluble vitamins can be toxic if taken in excess since your body stores them instead of peeing them out.

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1. Vitamin A

Vitamin A is essential for equipping you with a strong immune system. And vitamin A deficiency has also been linked to inflammatory conditions such as rheumatoid arthritis and type 1 diabetes. Why? Researchers seem to think this has to do with our dendritic cells. These alarms of the immune system can send out a "red alert" to stimulate immunity or a "calm down" message that tones down excessive immunity that can damage the body. The "calm down" message makes use of vitamin A. Vitamin A can be found in the following foods:

  • fish
  • shellfish
  • cod liver oil
  • liver
  • butter or ghee

Plant carotenes, a precursor to vitamin A, are found in sweet potatoes and carrots, but the conversion rate to the usable form of vitamin A (retinol) is very weak. In fact, research suggests that just 3 percent of beta-carotenes gets converted in a healthy adult.

2. Vitamin D

Known as the "sunshine vitamin," this nutrient is essential for many metabolic and immunological pathways in the body. For example, Th17 cells are helper T-cells that produce a number of inflammatory chemicals, such as interleukin-17. With autoimmune conditions—such as inflammatory bowel disease, multiple sclerosis, psoriasis, and rheumatoid arthritis—Th17 cells are out of control. But vitamin D, in conjunction with vitamin A, has been shown to synergistically dampen the Th17 inflammatory response.

As with vitamin A, vitamin D is most abundant in animal and dairy fats like:

  • mackerel
  • oysters
  • sardines
  • egg yolks

But soaking up some time in the sun is one of the best ways as well. Aim for about 20 to 60 minutes a day, depending on your complexion. And consider getting tests done every few months to ensure your vitamin D levels are healthy.

3. Vitamin E

Vitamin E refers to several nutrients known as tocopherols. While alpha-tocopherol seems to be the most bioavailable, beta-tocopherol, gamma-tocopherol, and delta-tocopherol all work synergistically in foods and in your body. Vitamin E is a powerful antioxidant needed to calm inflammation and support healthy, balanced immune and hormonal systems. Vitamin D can be found naturally in:

  • raw almonds
  • raw hazelnuts
  • wild salmon
  • palm kernel oil
  • flaxseed oil

4. Vitamin K2

Studies have found that vitamin K2 was effective at inhibiting the pro-inflammatory iNOS in the spinal cord and the brain immune system in rats that had multiple sclerosis symptoms. Unfortunately, K2 is one of the most common nutrient deficiencies in the Western diet. Vitamin K2 is best paired with the other fat-soluble vitamins—A and D—in whole-food form like grass-fed butter oil (ghee) or organ meat. Natto, a Japanese superfood made from non-GMO fermented soybeans, also has high levels of K2. Greens like cooked kale, raw Swiss chard, and dandelion greens all contain vitamin K1, and then our wonderful gut microbiomes convert K1 to K2. Another win for the gut bacteria!

When we're talking about vitamins and supplements, it's imperative to remember that food is primary. You can't supplement your way out of a poor diet that is devoid of real nutrients. Supplements are great, but we can't fully mimic the synergistic magic of nutrients in real food medicine inside a pill or a dropper. With that said, our food supply is not what it once was, lacking the nutrient content it used to contain. When it comes to supplements, it's all about balance. I always recommend getting lab work done before starting a supplement regimen, so you can design a plan that will be as targeted as possible.

Looking for a new supplement? Read this first.

William Cole, IFMCP, DNM, D.C.
William Cole, IFMCP, DNM, D.C.

Will Cole, IFMCP, DNM, D.C., is a leading functional medicine expert who consults people around the globe, starting one of the first functional medicine telehealth centers in the world. Named one of the top 50 functional and integrative doctors in the nation, Dr. Will Cole provides a functional medicine approach for thyroid issues, autoimmune conditions, hormonal imbalances, digestive disorders, and brain problems. He is the host of the popular The Art Of Being Well podcast and the New York Times bestselling author of Intuitive Fasting, Ketotarian,The Inflammation Spectrum, and the brand new book Gut Feelings: Healing the Shame-Fueled Relationship Between What You Eat and How You Feel.

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