Few topics are more debated in health than the value of the humble bathroom scale. Some experts advocate daily self-weighing to promote accountability for weight management, particularly when we’re following a diet and exercise program to lose weight.
Others suggest ditching self-weighing altogether, arguing that it can trigger negative psychological responses and unhealthy behaviors when you don’t like or understand the number you see on the scale.
Many, like me, recommend using scales to weigh yourself even when you’re not trying to lose weight. Here’s why.
Weigh yourself weekly
1. Weighing weekly helps you manage your weight
Research confirms regular self-weighing is an effective weight loss and management strategy, primarily because it helps increase awareness of your current weight and any changes.
A systematic review of 12 studies found participants who weighed themselves weekly or daily over several months lost 1–3 BMI (body mass index) units more and regained less weight than participants who didn’t weigh themselves frequently. The weight-loss benefit was evident with weekly weighing; there was no added benefit with daily weighing.
Self-weighing is an essential tool for weight management as you age. Adults tend to gain weight progressively through middle age. While the average gain is typically between 0.5-1kg per year [approx. 1-2 lbs], this modest accumulation can lead to obesity over time. Weekly weighing and keeping track of the results helps avoid unnecessary weight gain.
Tracking your weight can also help identify medical issues early. Dramatic changes can be an early sign of some conditions, including problems with your thyroid, digestion, and diabetes.
2. Weekly weighing accounts for normal fluctuations
Your body weight can fluctuate within a single day and across the days of the week. Studies show body weight fluctuates by 0.35 percent within the week and it’s typically higher after the weekend.
Daily and day-to-day body weight fluctuations have several causes, many linked to your body’s water content. The more common causes include:
The type of food you’ve consumed
When you’ve eaten a dinner higher in carbohydrates, you’ll weigh more the next day. This change is a result of your body temporarily carrying more water. You retain 3-4 grams of water per gram of carbohydrate consumed to store the energy you take from carbs.
Your water content also increases when you consume foods higher in salt. Your body tries to maintain a balance of sodium and water. When the concentration of salt in your bloodstream increases, a mechanism is triggered to restore balance by retaining water to dilute the excess salt.
Our food intake
Whether it’s 30 grams of nuts or 65 grams of lean meat, everything you eat and drink has weight, which increases your body weight temporarily while you digest and metabolize what you’ve consumed.
Your weight also tends to be lower first thing in the morning after your food intake has been restricted overnight and higher in the evening after your daily intake of food and drinks.
Exercise
If you weigh yourself at the gym after a workout, there’s a good chance you’ll weigh less due to sweat-induced fluid loss. The amount of water lost varies depending on things like your workout intensity and duration, the temperature and humidity, along with your sweat rate and hydration level. On average, you lose 1 liter [approx. 1 quart] of sweat during an hour of moderate-intensity exercise.
Hormonal changes
Fluctuations in hormones during your menstrual cycle can also affect fluid balance. Women may experience fluid retention and temporarily gain 0.5-2kg of weight at this time. Specifically, the luteal phase, which represents the second half of a woman’s cycle, results in a shift of fluid from your blood plasma to your cells, and bloating.
Bowel movements
Going to the bathroom can lead to small but immediate weight loss, as waste is eliminated from the body. While the amount lost will vary, you will generally eliminate around 100 grams of weight through your daily bowel movements.
All of these fluctuations are normal, and they’re not indicative of significant changes in your body fat or muscle mass. However, seeing these fluctuations can lead to unnecessary stress and a fixation with your weight.
3. Weekly weighing avoids scale obsession and weight-loss sabotage
Weighing too frequently can create an obsession with the number on the scales and do more harm than good.
Often, your reaction when you see this number not moving in the direction you want or expect is to further restrict your food intake or embark on fad dieting. Along with not being enjoyable or sustainable, fad diets also ultimately increase your weight gain rather than reverse it.
This was confirmed in a long-term study comparing intentional weight loss among more than 4,000 twins. The researchers found the likelihood of becoming overweight by the age of 25 was significantly greater for a twin who dieted to lose 5kg or more. This suggests frequent dieting makes you more susceptible to weight gain and prone to future weight gain.
So what should you do?
Weighing yourself weekly gives a more accurate measure of your weight trends over time.
Aim to weigh yourself on the same day, at the same time, and in the same environment each week — for example, first thing every Friday morning when you’re getting ready to take a shower, after you’ve gone to the bathroom, but before you’ve drunk or eaten anything.
Use the best quality scales you can afford. Change the batteries regularly and check their accuracy using a “known” weight — for example, a 10 kg weight plate. Place the “known” weight on the scale and check that the measurement aligns with it.
Remember, the number on the scale is just one part of health and weight management. Focusing solely on it can overshadow other indicators, such as how your clothes fit. It’s also essential to pay equal attention to how you’re feeling, physically and emotionally.
Stop weighing yourself — at any time interval — if it’s triggering anxiety or stress, and get in touch with a healthcare professional to discuss this.
At the Boden Group, Charles Perkins Centre, we are studying the science of obesity and running clinical trials for weight loss. You can register here to express your interest.
Nick Fuller, Charles Perkins Centre Research Program Leader, University of Sydney
This article is republished from The Conversation under a Creative Commons license. Read the original article.
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