Sometimes, confidence and weight loss go hand in hand, but sometimes it doesn’t. People often think that once you lose weight, you will be happier. Being healthier may give you more energy which may turn into more confidence. However, sometimes, people get sad after losing weight for one reason or another. Then their confidence may not be better. Losing weight may make people want to do more things. When someone can do more things like exercising or hiking a mountain, then that alone will give them more confidence.
So, I don’t think that losing weight brings more confidence. Instead, the loss of weight allows the person to do more activities and then this allowance of activities provides more confidence to the person.