How can you lose at least 15 pounds without anyone knowing?

If you don't want anyone to know you are on a diet, then just don't say anything about it. If you go out and eat, eat well, but have things like chicken or seafood, salad, veggies, etc., (red meat won't hurt once in a while) and pass up on the cake, cookies, pop, etc. It's OK to have a drink on the weekend if you want. You might want to use"Weight Watchers" which is really "corrective eating habits" and it's healthy for you too. Doesn't feel like a diet at all and not hard to stick too. No, I'm not working or plugging "Weight Watchers" but lost over 40 lbs., on it.

Going to the gym is the "in thing" now, so it wouldn't look odd if you decided to go. It's great for people to keep themselves in shape.

Drink plenty of water and stay away from pasta, bread, butter, gravies, sweets, etc. Even if you only lose a pound a week, pick up a pound of butter and that's how much fat you have lost! Also, men lose weight faster than women as they have less body fat.

and good luck!

Don't mention dieting. Most people need to see your bones before they'll comment on any weight loss. Weight gain however... seems like every pound gets its own sweet sixteen party, at least around here. I can work as hard as I can to lose weight, no dice. Gain a pound? and I am getting faaaat.