Bioavailability is the amount of a nutrient that is available for absorption into the large intestine and for the body to subsequently utilise - it is measured by the rate the supplement is absorbed into the body after consumption.
Just because you take a certain strength/dose of a supplement that doesn't necessarily mean that your body will get all of it to use.
You could buy a more expensive, lower strength supplement and gain more benefit than a higher strength cheaper alternative.
What does it depend on?
There are three main factors which affect the bioavailability of a supplement:
- How it has been formulated
- How it has been administered i.e. the type of tablet/capsule/caplet etc
- The quality of the supplement
Other factors include:
The quality of your vitamins and supplements is paramount - a poor quality supplement can mean that your body excretes a large proportion because it can't be absorbed efficiently. If it is excreted it cannot be used by the body.
High bioavailability indicates:
- A good quality, well formulated supplement
- A high proportion of the strength is utilised and absorbed by the body
- A poorer quality, cheaply formulated supplement
- A smaller proportion of the strength is utilised and absorbed by the body
Don't be fooled by cheap and mass produced supplements - be wary and investigate the quality of your supplier. You could literally be peeing your money away!