CBD bioavailability

by for the Ageless Team August 01, 2020

Bioavailability of CBD Products-for the Ageless

In some CBD products, most of the CBD you consume will be destroyed before it reaches your bloodstream. How much survives for your body to utilise, is known as bioavailability. Bioavailability can be increased or decreased depending on how you take it.

Understanding how 'bioavailable' a product is, gives you valuable insight into how effective it will be.

What is bioavailability?

The bioavailability of any product refers to the amount of the active ingredient that will reach your bloodstream once you’ve consumed it. Once it's been absorbed into your blood, it can be transported around your body to be used in your cells and tissues.

The bioavailability most often depends on the type of product and how it is been taken. Most methods of taking CBD only allow a limited amount of cannabidiol to reach your bloodstream. Some is broken down on the way or lost through other bodily processes.

If CBD were injected directly into your blood vessels, the bioavailability would be 100% because the full measure could be used in your body. Most other methods of taking CBD involve longer journeys to reach your blood resulting in a lower portion surviving. 

Please note: We do not recommend that you inject CBD under any circumstances.

Bioavailability offers a useful way of estimating how effective a product might be. If it is highly bioavailable, more CBD can be used. Products with low bioavailability will deliver a small amount to your system and will need to be taken in larger amounts to produce a potent effect.

CBD Oil Bioavailability

CBD absorption: fast facts

  • CBD can be absorbed sublingually, through the skin, orally, rectally and inhaled.
  • The most bioavailable form of CBD is an e-liquid/vape juice. Up to 56% bioavailability. 
  • You can make CBD more bioavailable by consuming it with a fat such as MCT oil.
  • CBD can be absorbed in as little as 10 minutes when inhaled. Absorption can take up to two hours if eaten.

Bioavailability of different CBD products 

There are hundreds of different CBD products to choose from, but they are all likely to be used in one of five ways: eaten, inhaled, absorbed under your tongue, inserted rectally or applied to your skin.

Each method transports CBD into your body but has a different rate of absorption. Different types of product deliver varying percentages of the original measure to your blood. The time it takes for you to feel any effect is likely to be different too.

The most efficient method for CBD absorption is to inhale the vapour using a vaporiser, which can deliver up to 56% of each measure to your bloodstream. This is a significant improvement compared to the 4-20% that is absorbed when you eat CBD.

CBD bioavailability chart

Method used

Uptake into your bloodstream

Time to take effect

1. Swallowed / ingested

4 – 20%

30 minutes – 2 hours

2. Sublingually (under the tongue)

35%

15 – 25 minutes

3. Rectally

8 – 50%

20 – 60 minutes

4. Inhaled or vaporised

Up to 56%

10 – 20 minutes

5. Topically (rubbed into the skin)

Can be up to 45% but stays localised (enters local tissue & small blood vessels only).

25 – 45 minutes

1. CBD drinks or edibles

CBD gummiesAny CBD product that is eaten or drunk must pass through your digestive system and your liver. This process has significant waste which is why only 4-20% of the CBD is available for use in your body.

Although you need to use more significant amounts of CBD to get the effect you want, these products are still popular. Capsules, drinks, edibles are convenient, discreet and can be flavoured to disguise the taste of the hemp extract.

2. CBD drops held under your tongue

CBD Sublingual applicationHolding CBD under your tongue allows it to be absorbed across the thin membrane directly into the blood vessels. This means that it isn't broken down in your digestive system, so there is a more significant amount available for use.

This method is most effective with liquid products like oils or tinctures. The desired number of drops is held under your tongue for 1 to 3 minutes and then swallowed. This can result in up to 35% bioavailability which is significantly better than just swallowing it.

The drawback with this method is that some products are hard to place under your tongue accurately and holding CBD in your mouth can produce an intensely bitter flavour. Finding a product with an accurate dropper or standing in front of a mirror to apply the drops can make it easier to deliver a precise measure. Also, holding oil under your tongue dulls the intensity of the flavour compared to holding it in your mouth as usual.

3. CBD suppositories inserted rectally

Because a large number of blood vessels in your rectum are close to the surface, CBD suppositories can have a bioavailability of up to 50%. However, products that can be used in this way aren't easy to find and most people prefer not to use suppositories if there are other options available.

4. Vaporised or inhaled into your lungs

Dry herb CBD vapeVape oils, e-liquids and the dry herb are turned into tiny airborne droplets in a vaporiser. They can then be inhaled, drawing the CBD particles into your lungs. Then they cross the thin mucus membrane into your lung's blood supply.

Your lungs provide a surface area of up to 75 square metres, which makes absorption into your blood quick and easy. The blood that passes through them picks up the CBD, travels to your heart and then around your body before it passes through the liver. This results in a large portion of each inhalation being available for use in your body.

CBD products burnt and smoked

Smoking CBD uses combustion to release particles that can be inhaled. The bioavailability can reach 31%, but you will also be inhaling other by-products (e.g. carcinogens) in the smoke. Also, when hemp or CBD flower burns, some of the cannabinoids are destroyed in the combustion resulting in it being far less efficient than vaping.

5. Rubbing CBD into your skin

CBD cream
Rubbing CBD into your skin is best when you're aiming to target a specific area. A small amount may reach your bloodstream but not enough to provide any noticeable whole-body effects. Topical CBD is often added to skin care products or rubbed into joints and muscles.

Ways to increase bioavailability

To ensure you get the most out of every CBD product, there are some easy ways to boost the amount that reaches your blood:

Hold drinks and edibles under your tongue before swallowing

CBD drink
If you're consuming CBD in a drink, oil, capsule or gummy, hold it under your tongue for 1 to 3 minutes before swallowing it. Biting open a soft gel capsule first will release the contents and increase the likelihood they can be absorbed sublingually. Gummies or other soft edibles can be vigorously chewed and then held under your tongue for better bioavailability.

Take CBD with a fatty meal

having fatty meal
CBD dissolves well in fats so if you eat it combined with fat or follow it up with a fatty meal. It's been found that more will survive the passage through your digestive system. Studies found that compared to taking CBD on an empty stomach, taking it with fat could increase the amount in your body by four times.

Choose water-soluble CBD products

water soluble CBD
Water soluble CBD
 is likely to provide a better bioavailability than those made with oil. It is specially prepared to pass quickly across your gut wall and miss out the first stage of digestion. It's still broken down to some degree, but studies have found that the resulting concentration in your blood is higher than with standard oil preparations.

Conclusion

CBD affects each person in a slightly different way but knowing how much of each measure will reach your blood for use in your body, will help you to make better-informed decisions about what to buy and how to use it.

Vaping or holding CBD under your tongue are the best ways to get CBD into your system and as a result, are likely to be more cost-effective than other methods.

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for the Ageless Team
for the Ageless Team

Author

We are a small but mighty team of experienced natural health researchers. We follow strict selection criteria and test everything we retail: from ground-breaking food supplements to natural skincare products. Our main area of expertise is CBD.


1 Response

Rao Zahid Umer
Rao Zahid Umer

January 08, 2023

You might mention negative aspects of vaping too, if any. as usually vaping is linked with many hazardous health issues especially related to lung health.

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