Why 90% of Your Supplement Goes Straight to the Toilet?

Health-conscious people who take supplements hardly think if they are absorbing them. People take supplements by assessing their diet, testing their blood, and checking the labels. However, most of them aren’t aware that the supplements they swallow never reach their blood and go straight to the toilet. So what happens to supplements between your mouth and bloodstream, and how do they get absorbed in your body? Here, you will learn the most relevant things. Let’s dive in. 

What Does Absorption Actually Mean? 

Supplement absorption is the process by which the human body breaks down a dietary supplement and passes its nutrients from the digestive tract to the bloodstream. The portion successfully entering the bloodstream, known as bioavailability, can be stored or used at a cellular level. Bioavailability is the percentage of a nutrient that really enters your bloodstream and gets available for your body to use. A supplement works like a delivery order. A restaurant lacks the full portion of food but 90% of it gets eaten on the way by the time it reaches the destination. The number on the label is what goes inside your mouth. Bioavailability is what genuinely reaches your body cells. 

The Journey of a Supplement — From Your Mouth to Your Blood 

Supplement absorption starts as the capsule dissolves in your stomach. Then, the supplement's active nutrients pass to the small intestine where special cells transfer them via the intestinal wall to the lymphatic system/bloodstream to be distributed across your body. 

The points below reflect the journey of a supplement from your mouth to your blood: 

Mouth to Stomach 

Acid starts breaking the capsule and passes its ingredients down. 

Stomach to Small Intestine 

This is the gatekeeper where almost all the absorption occurs.

Intestinal Wall 

The nutrients should physically cross from the gut into the bloodstream and most people don't make it.

Liver (First-Pass Metabolism) 

The liver can intercept even what crosses the gut wall destroying 40 to 80% of some nutrients before they reach the circulation. 

Bloodstream that works can survive all the things above. 

Why Most Supplements Lose the Battle Before They Begin

Most supplements tend to fail even before they start working because they face complications in absorption, digestion, formulation, and everyday consistency. Many pills pass through the digestive tract properly, lack the required cofactors for bodily uptake, or lose efficiency before they are consumed. 

The table below shows the comparison of different absorption killers and what occurs respectively. 

 

The Bioavailability Numbers Most Brands Hope You Never See

Bioavailability, the proportion of nutrients that the body uses tends to be low in mass-market supplements. Substances, like curcumin, sometimes offer limited absorption and some plant proteins have varied digestibility. The table below shows the approximate absorption of different nutrients in cheap and better forms. 

So What Should You Actually Be Asking About Your Supplement?     

     
Before starting to take any supplement, you should ask these important questions:

What form is the main ingredient in? 

The form of a supplement matters more than the dosage. 

Does the formula include anything to help absorption? 

Most formulas don’t include anything to help absorption 

Is the dose at a clinically relevant level, or just enough to appear on the label?

You should check if the dose is at a clinically relevant level or only enough to show on the label. 

Do I Actually Need This?

You should know if you are filling a genuine deficiency. 

Is it Safe for me? 

Safety shouldn't be compromised when taking a supplement and you should know if it interacts with your current medicines. 

Evaluating a supplement before taking it is crucial, which requires you to look past the advertising claims and examine the product itself. 

FAQs 

Q: What percentage of a supplement is actually absorbed by the body?

The body usually absorbs  20% to 50% of normal oral vitamin and mineral supplements. Bioavailability largely varies depending on the nutrient and its type. For instance, vitamin A supplements get absorbed at 70% to 90%, vitamin B12 reduces from 50% to even 2% at higher doses, and vitamin C gets absorbed by approximately 30%.     

Q: Does taking supplements with food improve absorption?

Yes, taking certain supplements with food improves absorption and helps in preventing stomach upset. Food stimulates stomach acid and digestive enzymes required to break down capsules.  Healthy diet fats work as a carrier for fat-soluble nutrients.

Q: Which vitamins and minerals have the worst absorption rates?

Nutrients with the poorest absorption rates are primarily certain minerals bound to plant compounds (e.g., non-heme iron, zinc) and poorly formulated supplements like magnesium oxide (which can have absorption rates as low as 3%). Low stomach acid (hydrochloric acid) is one of the key reasons vitamins don't work. You can't absorb minerals or break proteins to release vitamin B12 if your stomach pH is too acidic. You may have low stomach acid if you experience indigestion, SIBO, or heartburn. Antacids make absorption much worse. 

Q: What is bioavailability and why does it matter for supplements? 

Bioavailability is the element of an ingested nutrient, which smoothly eliminates digestion breakdown, crosses the intestinal boundary, enters the circulatory system, and gets ready for your body to utilize. A supplement having a high dosage has zero therapeutic value if your body can’t absorb it. 

Here are the key reasons why bioavailability matters for supplements: 

• Value and efficiency 

• Excess dosage prevention 

• Targeted delivery 

Q: Why does the form of a supplement ingredient matter more than the dose? 

The form of a supplement ingredient matters more than the dose because it assesses bioavailability, the percentage of the nutrient your body can absorb and use. A high dosage of poorly absorbed types of supplements will simply be excreted. While, a lower dosage of a superior type can deliver the desired results.