siameasy but it's not potatoes that you miss, it's the very risky combination of potatoes and fat. Plain boiled potatoes are quite dull, even freshly dug new potatoes. I guess what you're craving is the carb-fat combo of roast potatoes, crisps, potatoes mashed with loads of butter, rosti, dauphinoise... Just don't go there.
MrsTerryPratchett is right, our bodies were designed to eat meat & fish and plants that grew above ground, plus we had a marvellous system which meant that if our 'tribe' found a honeycomb we could gorge ourselves, and our insulin reaction would kick in and regulate our blood sugar (so we didn't die). However this was supposed to happen once or twice a year, at most. Not 2/3/4/5 times a day, which is what happens in a Western diet (and that continual insulin response is what contributes massively to metabolic disease.. diabetes, high blood pressure, etc.)
CalamityJune you and your growing baby need every variety of nutrients available, so please don't be overly restrictive. e.g. on a keto diet I wouldn't eat sweet potato, but it might contain something that you really need... However, as a principle (and this is sometimes how I explain my eating to other people) not eating sugar, or things that turn quickly into sugar, is good. So nothing like cake, biscuit (your growing baby won't miss these). But also take a few high carb things and keep them in your mouth for a while... you'll find that bread, pasta soon start to have a sweet taste - even without being digested, your saliva is breaking down the carbs very quickly into sugar. Avoid those.
Bears and hedgehogs get fat. But they get fat for a season (and a reason). Another season they are very lean. Most humans don't do that. We don't eat everything in sight until November and then stop for 3 months! In fact we do the opposite, we try to lose weight in the natural season of plenty, so we can stuff our faces with artificial crap at Christmas!