Loss of weight is directly proportional to the rate at which the disease is progressing.

体重减轻和该病的发展速度成比例。

《柯林斯英汉双解大词典》

KF: What is a reasonable rate of weight loss?

KF：减肥合理的速度是？

youdao

I've lost 15 pounds in the last few months, which isn't rapid weight loss but is actually a very healthy rate of loss.

过去几个月里，我一共减了15磅，减得不算快，但是确实不会伤身体。

youdao

Your two-pound-per-week rate of weight loss is safe and healthy, so I'm not concerned that you have lost weight too quickly, leading to a plateau.

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