Chronic Weight Fluctuation: Understanding and Managing Weight Changes

We have probably all been there. The point of frustration when you made goals to take better care of your body, and worked so hard to do so, but when you step on the scale it doesn’t read what you were hoping for.

The truth is that body weight fluctuates over months or years and even at different points throughout the day.  There are many reasons why this occurs. For healthy people, these weight fluctuations are considered normal. There are instances where significant weight fluctuations can occur due to a chronic illness, and signify a need for medical attention.

This article reviews weight fluctuation, understanding what is a normal weight fluctuation and how to manage weight changes.

How Much Weight Fluctuation is Normal?

It is normal for your body weight to fluctuate throughout the day by up to five pounds. Throughout the day, weight is gained through the food and drinks we consume. Weight is also lost throughout the day via urine, feces, and sweat. 

For people trying to lose weight, checking your weight daily is often suggested. What are often normal fluctuations can be frustrating. A person may be down a few pounds one day and up three pounds the next. It is also common that you may weigh more later in the day than you do in the morning or more on a Sunday than you would on during the week¹.

Extreme weight fluctuation exceeds 5 pounds in a single day, it may be cause for concern and should be discussed with a healthcare provider.

Why Does My Weight Fluctuate So Much?

Your weight will fluctuate depending on what you eat and drink, how you exercise, whether you are well hydrated, and certain medications that you may be taking.

Diet

A sustainable diet for weight fluctuation focuses on more than just calories. 

For example, choosing oatmeal with some added protein (for example, milk, greek yogurt, or a nut butter) and fruit for breakfast provides more nutritional value than a simple low calorie snack bar. In this example, the oatmeal with milk and strawberries for breakfast provides fiber, protein, calcium, vitamin D and vitamin C and is more likely to keep you satiated until the next meal. Snack bars sometimes contain added protein or fiber but they also may have added sugars and not as many vitamins or minerals. 

Eating a healthy breakfast is also said to help with weight maintenance².

Highly salted or sweetened foods can cause the body to retain more water. Foods high in sugar also tend to be higher in calories making long term weight loss a challenge. 

If you are following a diet regimen that encourages “cheat days”, you may notice your weight going up the next day. A knee-jerk reaction might blame this weight increase on the calories you ate, but it’s more likely due to the water retention after eating salty sugary and high fat foods. Such fluctuations in the diet can lead to fluctuations in weight.

Exercise

Maintaining a negative energy balance will result in weight loss. A safe amount of weight loss is 1-2 pounds weekly. Depending on the type of exercise you are doing and your hydration status, weight fluctuations can occur over shorter periods of time (less than a week). 

For example, it is normal that people gain some weight when initially starting out with a weight training regimen to build muscle. Some may find they lose weight after strenuous exercise but this is really just a result of sweat loss and dehydration if you did not drink enough water throughout the activity.

Hormonal Changes

Changes to the female body that occur just prior to or during the menstrual cycle cause the body to retain more water. Fluid retention and swelling is a common complaint among females during their menstrual cycle³. This leads to a weight gain of about 3-5 pounds on average. The weight gain is normal since it is water and not body fat that is gained. Additionally, your weight will fluctuate back down once your period starts. 

Some may also consume more calories during certain periods of their menstrual cycle⁴.

Medications

Some medications can cause an increase in appetite or promote more water retention, which can lead to weight fluctuations. These medications include: 

• Insulin. 
• Thiazolidinediones.
• Beta-adrenergic blockers.
• Tricyclic antidepressants.
• Selective serotonin reuptake inhibitors.
• Lithium. 

If you think a medication is causing weight fluctuations, you should discuss with your healthcare provider.

Illness

Weight loss after a bout of acute illness is temporary. Diarrhea or vomiting can lead to dehydration and food intake is typically less when people are ill. The weight lost often returns after recovery.

Some chronic conditions may also lead to unexplained weight changes. Significant unexplained weight changes that are outside the range of normal weight fluctuations should be discussed with a healthcare provider. 

For example, people with heart failure or kidney failure experience a lot of weight fluctuation with fluid shifts, diuretic use, and dialysis treatment and they require close monitoring by a physician.

Weight Cycling

Weight cycling is the term used for people who frequently diet with temporary success, but eventually gain the weight back after stopping the diet. Another term for this is yo-yo dieting.

Weight fluctuation often occurs in this instance. However, weight fluctuations associated with yo-yo dieting are typically larger than what is considered normal weight fluctuation. 

Some preliminary research suggests that this type of weight fluctuation can have negative health consequences. One review found that weight fluctuations were associated with an increased risk of cardiovascular disease (CVD), death from a CVD event, and all cause mortality⁵.

The studies included in this review looked at weight fluctuations that were mostly between 2-20% weight change (this would equate to a 3-30 pound weight change in a 150 pound person). Further studies similarly found that weight fluctuations were associated with a greater risk of all-cause mortality⁶ and were a strong predictor of developing diabetes⁷.

While this suggests that frequent weight cycling or yo-yo dieting could be hazardous to your health, more research still needs to be done. In the meantime, it is important to find a healthful way of eating that supports safe weight loss and can be  sustained over a lifetime.

How Can I Minimize Weight Fluctuations?

1. Consider a weight monitoring regimen that works best for you. Some people prefer to check their weight daily. Others may be too frustrated with daily fluctuations and find weekly weight checks are better for them. Either way, understanding normal weight fluctuations should eliminate frustrations. If you have a history of eating disorders, avoid checking your weight.

2. Don’t allow the normal weight fluctuations to spiral you into giving up. 

3. When you do step on the scale be sure you do so at the same time of day, same day of the week, and using the same scale.

4. Consider other measures rather than just weight and body mass index (BMI) to monitor your progress. BMI is your weight in kilograms (kg) divided by your height in meters squared. It is used frequently as a quick assessment of body weight but it doesn’t take into consideration a person's lean body mass vs fat mass. Even with weight fluctuations and little weight loss, body composition measurements may improve significantly. Other measurements include waist circumference, thigh circumference, or body fat percentage.

5. Follow a healthy diet that is sustainable and can be followed for the rest of your life. Include plenty of high fiber foods⁸ and fruits and vegetables² to be sure you are getting potassium and magnesium in your diet. Eating foods high in potassium and magnesium will simultaneously limit the amount of sodium in your diet but potassium and magnesium also play a role in sodium balance in the body.

6. Eat a healthy breakfast. Doing so has been shown to help with healthy weight maintenance².

7. Avoid diets that are too restrictive or include “cheat days”. Diets that are too restrictive or eliminate entire groups of food are challenging to follow over the long term. The idea of “cheat days” allows for any food which often tends to be higher in fat, sugar, or salt leading to greater fluid retention.

8. Limit salt, alcohol, and high sugar foods. Instead, opt for foods high in protein. These include lean meats, legumes and pulses, nuts and seeds, and seafood. A higher protein intake appears to play a role in weight management⁹.

9. Be consistent with physical activity and build a routine that works for your schedule. Physical activity may be the most important variable in maintaining weight loss^2,8. Exercise that both raises your heart rate and builds muscle is recommended. Find a form of physical activity that you enjoy doing, or enlist the help of a friend to join you as an accountability partner. Avoid unreasonable or excessive exercise regimens that are likely to lead to an all or nothing approach.

Nourish Is Here To Help

It is normal to experience weight fluctuation to some degree. A Registered Dietitian trained in weight management can help you avoid future fluctuations. Together you can build a health plan that will help you achieve long lasting results.  

Nourish has a large team of RDs who are expertly trained and want to help you succeed. The appointments are virtual and can seamlessly fit into your schedule. Did we mention they’re also covered by insurance? Click here to get started with Nourish today! 

References:

1. Weight rhythms: weight increases during weekends and decreases during weekdays.
2. Successful weight loss maintenance: A systematic review of weight control registries.
3. Characterization of symptoms and edema distribution in premenstrual syndrome.
4. Changes in macronutrient, micronutrient, and food group intakes throughout the menstrual cycle in healthy, premenopausal women.
5. Body-Weight Fluctuation Was Associated With Increased Risk for Cardiovascular Disease, All-Cause and Cardiovascular Mortality: A Systematic Review and Meta-Analysis.
6. The association between weight fluctuation and all-cause mortality: A systematic review and meta-analysis.
7. Association between weight cycling and risk of developing diabetes in adults: A systematic review and meta-analysis.
8. Healthy strategies for successful weight loss and weight maintenance: a systematic review. ‍
9. Are Dietary Proteins the Key to Successful Body Weight Management? A Systematic Review and Meta-Analysis of Studies Assessing Body Weight Outcomes after Interventions with Increased Dietary Protein.