If you have one high-sodium meal and then return to normal, healthy dietary habits, you'll likely return to your normal weight in 1-2 days. If you're returning from a vacation of over-indulging and are retaining a higher amount of excess fluid, it may take longer.
It takes about two days to lose one to three pounds of water weight. But how fast excess water leaves the body can depend on diet and physical activity. The healthier your diet and the more physically active you are, the faster you can get rid of excess water.
Overnight, you are less likely to replace the water you lose through sweating and urinating. On average, you sweat about 25ml per hour of sleep under temperate conditions (around 85 degrees Fahrenheit). ² If you sleep for an average of eight hours, that's around 200ml of sweat per night.
Water retention, also known as edema, can show up as bloating, puffiness, swelling or unexplained weight gain over a short period of time. Edema is classified as pitting edema and non-pitting edema. In pitting edema, the swollen areas on your body respond to pressure from your hand or finger.
If your extremities such as your wrists, ankles or fingers are swelling, it's probably from water weight gain. If you've noticed your wrists or ankles are swollen or your rings are tighter than usual, that probably means you've retained some water.
Extra water is typically stored all over your body in the tissue or between blood vessels, and tends to pool in the extremities (fingers, toes and lower legs).
Fat mass doesn't change quickly, but you can lose as much as five pounds of water in a day. The average 24-hour urine loss is about 1.8-4.4 pounds because water is heavy. By contrast, it's virtually impossible to burn off a pound of fat in a day.
If you push on your skin with your finger or thumb and your skin remains depressed, you're probably experiencing water retention. Fat cells are more springy, so the skin will bounce back. Do you feel bloated after eating?
One more way to tell if you are losing water weight or having fat loss is, if you lose 1-kilo overnight, it's a clear indication that you can attribute that weight loss to water. Most people can lose 1 - 1.5 kilos of actual weight in a week and around 1 per cent of their body fat in a month.
Therefore, as we discuss the reasons why the scale reads that you gained weight overnight, the majority of rapid weight gain is water/food-related rather than actual fat tissue you've accumulated.
Reducing salt and carbohydrate intake, keeping hydrated, and frequently exercising are all good ways to lose water weight and prevent it from returning.
Press with your finger on your legs or hands and if the imprint remains or leaves an impression that lasts more than a few seconds, its water weight. Ideally, if you press, it should come back to its original shape immediately.
Bloating may occasionally add a pound or two, but it doesn't actually signify weight gain. A simple way to tell the difference between bloating and weight gain or fat is how your stomach looks and feels. If your stomach is tight and hard, then bloating is the cause. If your stomach is soft and thick, then that's fat.
That said, a person may experience sudden, noticeable weight loss if they lose a lot of water weight. They may also lose weight gradually when cutting calories or carbs but only notice the weight loss suddenly on the scale.
If you're trying to lose water weight, it may be time to stock up on bananas. “Potassium regulates sodium in the body and therefore may reduce water retention,” says Gans. “Foods high in potassium include avocados, pistachios, spinach, kale, sweet potatoes, mushrooms, artichokes, fennel, Brussels sprouts, and arugula.”
An average woman needs 2,000 calories every day if she rests and eats nothing (6). So, if you do not eat anything for 2 days, you will technically already have a 4,000 calorie deficit. That means you have just smidgen over one pound without eating anything for 48 hours.