Find Brands that overlap both "External" and "Internal" beauty

I am researching the overlap between - (A) externally-applied beauty products products: especially skin cream or sun cream, but could be hair care (shampoo, conditioner) , and - (B) vitamins/dietary supplements (especially those intended to improve beauty eg, skin, hair, nails etc) Therefore want to find a number of brands that are in *both* areas (As a follow-on project, if we find some, I will want to investigate them more) Suggested process: 1. For specific market (eg, start in USA) 2. Identify (A) beauty/ skincare brands… best to extract from Amazon USA? (search and extract the clean brandname from the results) probably aim to find 1000 brands? (there are over 50,000 results for "Beauty & Personal Care : Skin Care : " …maybe 50 individual products per brand, so 1000 brands) 3. Identify which brands sell vitamins/ supplements as well as beauty: either: check each of the 1000 brands' websites (the (A) brands found in step 1)to see whether they sell vitamins/ supplements - this is probably the most reliable way [ or: identify 1000 vitamin/supplement brands from amazon and compare the 2 lists] 4. It is also possible to find some brands through intelligent web-searching 5. Extract brief info for brands that do both name, website, name of example external product, name of example internal product (vitamin/ supplement) Payment could include a bonus (£5?) for every genuine overlap brand found up to 20