In terms of “Australia” and “men”, I would suggest using Adwords-keyword tool or similar tools to see what people are searching try mixing product/category with gender terms e.g. “vitamins men”, “vitamins man”, “vitamins male”. If people are searching for these phrases I would suggest using them in your anchor text. I would expect people to be searching for man or male relates health and fitness products.
When using Adwords remember to use Broad, Exact and phrases match types, to get the whole picture.
If your site is clear Australia site (.au) or it’s marked within Google Webmaster > Site Settings > Geographic target as Australian, then you will probably not need to include Australia in the anchor text. But please check first.
I would recommend varying your link text on external sites. You can get idea of alternative phrases from Google Adwords>Keyword tool, Google Suggestions and “related searches” on the Google search page, also use a thesaurus. When the link is in a paragraph sometimes consider using site name or click here, so Google & Bing will look are the surrounding text.
In terms of on-site, I would have anchor text, file names, title pages and h1 titles in line with each other (not necessary the same). So when a visitor navigates from Google/Bing to your site & through your site they feel that they are getting what they clinked on, while building a strong SEO optimisation of the key phrase for that page.
Hope this helps.
K