What Is The Difference Between Water Vs Fat “Soluble” Vitamins?

What Is The Difference Between Water Vs Fat “Soluble” Vitamins?

The Term “Soluble” means “able to be dissolved in.”

Typically we hear “Soluble” in reference to an items ability to be dissolved in water or alcohol (alcohol is another typical solvent)

When it comes to vitamins we have “fat-soluble” and “water-soluble”

Think of sugar and water: you can mix them into one substance.

Sugar and Water mixed
Water solubility explained: The two compounds are now joined as ONE.

Meaning that sugar was dissolved in the water, making sugar water-soluble.

Why does it matter whether or not vitamins are water-soluble or fat-soluble?

It’s due to the way that we store and get rid of them.

Vitamins are needed in varying quantities each day to prevent deficiencies and diseases.

Water soluble vitamins will circulate in our body water and get shuttled all over our body.

Once they’ve reached their destination they’ll swiftly be used by our tissues until they’re all depleted.

In most cases if we have an overabundance of water soluble vitamins they’ll be pushed out of our body when we use the restroom.

It’s also why some people see a BRIGHT yellow in their urine after taking a multivitamin.

(Fun Fact: The culprit to bright yellow urine is to due Riboflavin!)

Below I’ve made a table of The RDI of your water soluble vitamins

Table of Water Soluble Vitamins:

Vitamin B1 (Thiamin)(Men) 1.2mg(Women, Non-Pregnant) 1.1mg
Vitamin B2 (Riboflavin)(Men)1.3mg (Women, Non-Pregnant) 1.1mg
Vitamin B3 (Niacin)(Men) 16mg(Women, Non-Pregnant) 14mg
Vitamin B5 (Pantothenic Acid)(Men) 5mg(Women, Non-Pregnant) 5mg
Vitamin B6 (Pyridoxine)(Men) 1.3mg(Women, Non-Pregnant) 1.3mg
Vitamin B7 (Biotin)(Men) 30mcg(Women, Non-Pregnant) 30mcg
Vitamin B9 (Folate)(Men) 400mcg(Women, Non-Pregnant) 400mcg
Vitamin B12 (cobalamin)(Men) 2.4mcg(Women, Non-Pregnant) 2.4mcg
Vitamin C (Ascorbate/Ascorbic Acid)(Men) 90mg(Women, Non-Pregnant) 75mg
please note mg is not interchangable for mcg. MCG standard for micrograms, a smaller unit of measurement than mg.

PLEASE NOTE: Those are the GENERIC guidelines set forth for a GENERALLY RECCOMENDED DAILY INTAKE/or ADEQUATE level of intake for the general population.

It is not meant to provide optimal benefits or be maximally effective for your goals.

Individual goals require individual specific planning and outcomes and should be assessed by yourself and your primary care physician.

Those numbers indicate that barring any genetic or digestive issues, at that daily intake you should prevent deficiencies in those nutrients.

Lastly, you might experience nausea, flushing, or very inconvenient side effects from a bolus dose though they are typically not life-threatening.

It mostly takes CHRONIC exposure to elevated amounts of water-soluble vitamins to potentially incur problems.

(like a possible deficiency between folate or b12 occurring if you constantly over-dose those vitamins.)

Fat soluble vitamins require more attention.

Now, FAT soluble vitamins (FSV) are a MUCH more concerning the topic.

This is because these molecules do NOT dissolve in body water, they’ll firstly bind to.. you guessed it!

Fats!

These vitamins actually take a little while longer to transport and will become stored inside of our body for longer.

This means hat excess fat soluble vitamins can build-up and become toxic to our body.

(You may have recalled a fun party fact that if you were to eat a polar bears liver you would die of vitamin A poisoning.)

This isn’t to say you shouldn’t have ANY fat soluble vitamins or supplement if needed!

This is to help people be more mindful of their indiscriminate intake of supplements.

I’ve gone ahead and left a small table below of the Recommended Daily Intake (RDI) of our FSV’s to help give you all a generic reference. (Excluding Vitamin K, Vitamin K has an AI (Adequate Intake level)

Table Of Fat Soluble Vitamins

Vitamin A***(Men) 3000 IU(Women, Non-Pregnant) 2333 IU
Vitamin D* **(Men) 1500 IU(Women, Non-Pregnant) 1500 IU
Vitamin E(Men) 15 IU(Women, Non-Pregnant) 15 IU
Vitamin K(Men) 120mcg(Women, Non-Pregnant) 120mcg
*Please note Vitamin D is not delineated between D2 and D3, D3 is much more bioavailable. **Also, As you age you will need slightly more vitamin D for bone and hormonal health. *** Vitamin A gotten through plant food sources are not of concern for toxicity as the conversion process is limited heavily by the levels in the body. Non-preformed vitamin A will not cause toxicity.

Side note on Fat Soluble Vitamins

PLEASE NOTE: Those are the GENERIC guidelines set forth for a GENERALLY RECCOMENDED DAILY INTAKE/or ADEQUATE level of intake for the general population.

It is not meant to provide optimal benefits or be maximally effective for your goals.

Individual goals require individual specific planning and outcomes and should be assessed by yourself and your primary care physician.

Those numbers indicate that barring any genetic or digestive issues, at that daily intake you should prevent deficiencies in those nutrients.

Vitamin K is a special fat soluble vitamin

Photo by Eva Bronzini:

Also of note, Vitamin K is not set for an RDI/RDA, it is set for an Adequate Intake level (AI).

This is because Vitamin K is difficult to get data on nutritional measurements that definitively state an Estimated Average Requirement (EAR.)

It’s difficult to get an Average Requirement because of a few factors.

Vitamin K technically doesn’t refer to a SINGLE nutrient or compound.

Like the rest of the fat soluble vitamins it refers to a family of compounds with a shared named.

Vitamin K is classified by quinones, commonly you’ll find phylloquinone (which is K1) OR Menaquinones (K2, which is most common from my experience)

Mostly, the difficulty in getting an EAR is due to the variance in levels of blood tests in individuals.

In terms of finding how to detect deficiency, they don’t really know how to measure it effectively.

Essentially, based on multiple studies, researchers have a few general ideas of how specific quinones influence certain functions.

Quinones’ impact on our bodies ecosystem as a whole, however; is a bit unclear in the literature forthem to safely and accurately provide a DEFINITIVE universally acceptable answer.

Also, it’s partially because often researchers only clinically evaluate Vitamin K status when there is issues in blood clotting. (Vitamin K’s most essential role).

In Summary.

Now that we know how to generically lump these vitamins into TWO categories, we have a small baseline understanding of nutrition!

Don’t worry, I will have us examine each Vitamin/Mineral in depth in the future.

Even though those posts do not do particularly well, I like having them as references later on.

It will help make a guide based on their synergies easier to understand for readers.

For now, this just serves as a note of:

“Here is some FUNDAMENTAL but easy to understand information.”

no modes of transportation yet, no mechanism of actions, just good old
“open your textbook to page 8 learn what these terms mean.”

Lastly, to recap this whole post’s main message at the end:

Water soluble = generally safer to take, can take whenever.

Fat soluble = more attention required, best absorbed with fats in meal.

Citations:

Vitamin A | The Nutrition Source | Harvard T.H. Chan School of Public Health.

Vitamin E

https://ods.od.nih.gov/factsheets/VitaminK-HealthProfessional/

https://www.ncbi.nlm.nih.gov/books/NBK538510/

https://www.karger.com/Article/Abstract/362294

https://www.ncbi.nlm.nih.gov/books/NBK441912/

Leave a Reply

Your email address will not be published. Required fields are marked *