In and of itself scales won't make your weight fall off BUT if you want to lose weight, you will need scales to know what weight you are now and to know when you have attained the weight loss you desire.
Which ones to buy? I prefer digital scales with the smallest increment of 50g rather than 100g or 200g. They use a small battery - CR2032 I think. You can buy scales that do not use a battery. They use a spring mechanism. My opinion is that they are less reliable and less accurate. However, if you don't want battery operated scales and you are not too fussed about accuracy and just want a general guide to your weight, they might be a good choice for you. They are usually cheaper too. If you use the same scales in the same location, on the same surface and stand in the same way each time, most scales should be good enough for most people.
How often to weigh? Daily in the morning after urinating. Don't worry if your weight one day is higher than the day before. That can happen. It's best to note the trend over weeks - generally downwards, generally upwards or generally no movement at all. To remember your weight and to be able to note the trend upwards or downwards, you might want to record your weight on paper or some other way.
Good luck.
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