You step on the scale and are surprised to see you’re three pounds heavier than you were yesterday. Yikes! In panic mode, you quickly review your diet. What could have caused you to “balloon up” overnight? Relax. It’s not uncommon for weight to fluctuate by a few pounds from day to day. After a very large meal, you may find the scale reads as much as three or four pounds higher. Before assuming that what you’re doing is not working, consider these five common reasons for day to day weight fluctuations.
You Pigged Out the Day Before
If you had a splurge meal and ate a significant amount of food, you may see your weight jump by as much as a few pounds – but it’s not body fat unless you managed to eat 3,500 extra calories during your splurge. In fact, unless you’ve been having frequent “cheat meals,” that extra weight will disappear in a few days. What accounts for the increase? Increased glycogen stores from a higher carb meal than what you typically eat is one cause. When you store a gram of glycogen, several grams of water are stored along with it, which increases your weight. Another reason your weight may be higher after a big meal, especially one high in salt, is fluid retention.
Fluid Retention Due to Salt
If you splurge by eating a meal at a restaurant or a fast-food meal, you probably took in more salt than you usually do. When you take in too much sodium, your body holds onto water. This leads to temporary weight gain and bloating. It sounds counterintuitive, but the best way to eliminate excess fluid and weight is to drink more water. Eating potassium-rich foods like fruits and vegetables also helps with fluid retention. After eating at a restaurant, cut back on your sodium the next day to compensate.
It’s not a fun subject to talk about, but constipation can cause temporary weight gain. When food accumulates in the large intestine, it can tip the scales higher until you have a bowel movement. To prevent this cause of weight gain, eat more fiber-rich fruits and vegetables. Another option is to add a teaspoon of psyllium husks to your morning cereal. You can buy psyllium in the bulk section of some natural food markets and health food stores. Drinking more water also helps with constipation.
You’ve Just Eaten
It’s normal for your weight to go up after eating a meal. After all, food and beverages have weight and temporarily tip the scales higher. Don’t make it a practice to weigh after a meal, because you probably won’t like what you see. Weigh first thing in the morning before eating or drinking anything for the most accurate reading.
In women, estrogen and progesterone levels fluctuate on a monthly basis. These hormones can cause monthly cycles of fluid retention as well as affect neurotransmitters that control mood and appetite. Some women report weight gain and cravings for carbs a week before their period. Birth control pills also cause fluid retention in some women and can lead to water weight gain. Contrary to popular belief, most studies show that oral contraceptive pills are not a significant cause of non-water weight gain.
There’s not much you can do to prevent monthly weight changes related to hormonal fluctuations except limit the amount of salt in your diet, increase the number of potassium-rich foods you eat and drink lots of water.
The Bottom Line?
Fluctuations in weight of several pounds from day to day are not uncommon. One way to avoid becoming obsessed with a number is to weigh only once or twice a week. Weigh first thing in the morning before eating, drinking or getting dressed. If you’ve had a splurge meal or you’re pre-menstrual take that into account when interpreting your weight. More importantly, don’t make the scale your primary focus. Other things like how your clothes fit and how you look in the mirror are more important.
Contraception. 1998 Dec;58(6):345-9.