[LilacTofu]

Super unpopular opinion here, but I think you should totally create your own diet for your ham if you'd like, and you can even do it without calculating every little detail, too. Just think about it for a moment: do you honestly know what the exact percentage of protein, fat and fiber is in every single meal you eat? Do you actually know how much calcium there is in your dessert? The answer is no, but you're still very much alive and most likely not suffering from any illnesses related to your diet.

The key is actual variety as opposed to a standardized mix. Wild hamsters don't eat a specific ratio of this and this and some of that. They eat whatever they can find and it just so happens that things usually balance out over time because there is quite a bit more variety in the wild than there is in most captive diets because of the seasonality of food and because of the opportunistic nature of rodents in general.

So yes, it's not a good idea to create a mix if you don't know everything there is to know about the nutritional needs of your hamster, but you don't have to create a mix to be feeding her properly. Just feed her.. food. Lots and lots of different food. Omit anything that's unhealthy (refined grains, sugar, greasy people food .etc.) or toxic (alliums, chocolate, bitter almonds .etc.) and feed with a bit of an eye toward what she's getting from that food.

Maybe give her a dollop of unsweetened yogurt for some natural vitamin b12 one day, then give her some spinach and collards for calcium, iron, vit C and such the next, then give her some cooked beans for fiber and so on.
Offer a variety of grains, such as oats, millet, flakes of barley .etc. and limit fattier additions like sunflower seeds and flax and don't worry so much about the numbers. Just use common sense like you do with yourself and your family. As to where you should source your foods.. the hamster doesn't mind either way, but health food stores are a pretty good place to start. One small bag of oats or buckwheat will last pretty much forever and you're paying for quality, human grade items. When you buy a package of hamster food? Not so much.

True, your hamster won't eat everything you give them, but that's not necessarily a problem if you're offering them a wide range of foods. There is more than one source of calcium for example in a diet based upon variety whether that source is sardines w/ bones, sesame seeds or broccoli. My syrian boy, Nibs, eats NO commercial foods whatsoever. This evening he had fresh basil and oregano, green cabbage, some carrot, frozen blueberries, half a strawberry, a bit of yogurt and one drop of extra virgin olive oil. He had some diluted tea as well which was mint tea and black tea brewed together 50/50 with no added sugar or milk/cream.

You also do not have to offer vegetables and fruits (well, I'd limit fruits if you had a dwarf heh) in tiny portions or in an infrequent manner imo. A majority of what Nibs eats is, in fact, made up of vegetables and fruits. He doesn't suffer from diarrhea due to the water content or any of that nonsense. Animals DO know what they need to an extent and they won't fail to eat enough calorie/protein rich foods, trust me. I'd also always research lists of "toxic/nono" foods you find on the internet because sometimes there's no basis/evidence behind people labeling a specific food as "toxic" and often you can find more information as to what is good or bad/toxic for a hamster by looking at research done on hamsters for one reason or another.

For example, alcohol is often listed as "toxic", but in actuality a lot of rodents (hamsters included, rats too) have a much higher tolerance to it than WE do and so long as you aren't actually getting your little friend drunk, a small sip here and there if they happen to like it isn't going to do.. anything really.. so it's not exactly toxic. Alcohol doesn't actually have any food value and I'm not suggesting we all start giving our hams shots of vodka or anything, but you get the point, yeah?