The phrase "adding a supplement" is correct and usable in written English.
It can be used when referring to the act of including additional information, materials, or resources to enhance or complete something.
Example: "The report was improved by adding a supplement that provided further data and analysis."
Alternatives: "including an addendum" or "providing an addition".
Rather than taking such supplements, it would be better to spend your money on vegetables and fruit – this will help to make your whole diet better rather than adding a supplement and not thinking about the food you actually eat.
Before adding a supplement to your diet, it's best to consult with a doctor.
"Any news about finding something simple -- like lifestyle, or adding a supplement -- to reduce the risk of breast cancer is important," said Savard.
While it is likely that you get enough vitamin B6 for normal function, adding a supplement of 100mg per day may increase the vividness and lucidness of your dreams.
Adding a supplement such as vitamin B6 to their diet also helps some women.
However, some vegans may need to add a supplement (specifically vitamin B12) to ensure they receive all the nutrients required.
I have added a Supplement of Proper Names, including some of the Greek equivalents for names famous in Roman History.
I don't mean literally illustrate -- that's not permitted in the Culture Audit, though you can add a supplement full of pics and video if you like -- but stories and quotes from individual employees as well as leaders can be the picture that's worth a thousand words.
We have added a supplement to Figure 2 showing an overlay of the electron density maps of wtPTE, AE, and neoPTE to support this claim.
If you decide to add a supplement to your daily diet, consult with a doctor or nutritionist first to make sure it's a healthy choice for you.
In the revised manuscript we have added a supplemental file (supplement 7) with individual samples IDs (TCGA barcodes) for easy reference.
