Keto week 1 down, 12.8 lbs down!

Congratulations on the loss! However, dont expect that trend to continue. You have lost a lot of water weight from a massive change in diet, most of which would come right back if you go back to your old ways. It is not possible for you to lose 12 lbs of fat in one week. That would need you to be in a deficit of roughly 42,000 calories. Which is more than most people eat in a week, obese or not.

All I'm trying to get across is dont be disappointed if next week you only lose 1 lb, or none at all, or even gain a little back. A lot of factors are in play here.

Also, just because you had a good whoosh of body weight loss over one week, this does not mean keto is better than any other plan. Just to point that out. Many people experience large weight loss in the first couple weeks after a large diet change. Mostly due to water loss because of sodium levels, carb intake and increased physical activity.

When you reduce carbs, your body depletes your glycogen stores. Glycogen is stored with water, so a large water weight is normal in the beginning of Keto. That does not mean that it is bad or is not weight (it's still weight your body carries around), but understand that that weight will only stay off as long as you continue doing Keto. If you hope to lose on Keto and then go back to the normal way of eating, you will replenish your glycogen stores and regain a lot of that lost water weight.

If you maintain a calorie deficit during keto, you will lose fat. This will take some time to accomplish and will happen over weeks and months, but just like any other diet, keto can be an effective weight loss tool, if you eat less than you burn. I am glad that you are happy with it so far, and hope that continues for you. Just wanted to give you some insight into why you are seeing the big drop you are.