What causes chronic fatigue and stubborn weight gain?

Sally is a 43-year-old woman. She came to see me for fatigue. She also experienced unwanted weight gain in the last couple of years. She was of average weight but slightly on the heavier side. 

She mentioned her weight wouldn’t budge despite eating a whole food-based diet and exercising 5 times weekly. She also noted she used to reset her weight and energy by using the keto diet. She sometimes alternated using the keto diet with intermittent fasting. Nonetheless, it stopped working this time. Now, even after adding exercise, the number on her scale stayed the same. She was frustrated and unsure what else to do. 

It’s rare that fatigue, or stubborn weight gain is caused by one thing. These two often go hand in hand, especially as you get older. 

Causes for fatigue and stubborn weight gain 

Unfortunately, the number one factor is aging or accelerated aging. As your body ages, your metabolism slows down. It works less efficiently and uses fat as an energy source. 

Hormones that maintain your metabolism also drop as well. These include your thyroid hormones, your stress hormones, your hunger and satiety hormones, and the most overlooked one, insulin. 

Your body becomes less sensitive to insulin as you age. As a result, you get tired more easily. You may notice increased cravings, and snacking for sweets, and an increase in abdominal fat. Other changes include dark pigmentation and skin tags under your armpits, neck or face. 

Finding the root cause of Sally’s problem

For Sally, after learning more about her case, I started her with a comprehensive lab to get a baseline assessment. This was to check for any nutrient imbalances, like low iron. 

Included in her lab test were biomarkers that help identify hormone related issues, like her thyroid health and poor stress responses. 

We also checked if there was a blood glucose problem that was preventing her from losing weight.  

Her lab results came back, and we discovered a number of abnormal findings.

Her fasting insulin levels were off the roof at 17 - the optimal range is between 6 and 10. This meant that her body was struggling to metabolise and use insulin effectively - also known as insulin resistance. Insulin usually helps move glucose from your blood to your cells or liver to use, or store as energy. When it’s not working properly, blood glucose gets stored as fat, leading to weight gain. 

Sally’s stress hormones were low - and while this might initially sound positive, stress levels are complex. Her lab results showed that stress was negatively impacting her physiological function. Her morning cortisol levels were 5, which barely makes the cut off point of the normal range, which is between 3.7 and 19. This suggested her body was struggling to make enough cortisol to get her day started in the morning - also known as burnout. In short, low cortisol levels should not be interpreted as meaning not stressed. Low cortisol levels often contribute to chronic fatigue.

Her lab results also showed her thyroid was starting to struggle. Your thyroid is a gland which governs your metabolism, producing hormones that regulate your mood, alertness, brain function, how quickly your body transforms food into energy, and how quickly energy from that process is used. Sally had elevated TSH (thyroid stimulating hormone) and normal fT3 and fT4, which meant her thyroid was not producing enough hormones  causing both weight gain and fatigue. 

The level of iron in Sally’s blood (serum iron) was normal, but her iron storage (also known as ferritin) came back low (in the red).  Iron is key for cellular energy, and low levels of ferritin demonstrate an iron imbalance that’s often missed from checking  blood serum levels alone.

Looking at these results, it was no wonder Sally felt tired and couldn’t lose weight.

In her follow up consultation, we reviewed her lab results line by line and I gave her an individualized treatment plan tailored to her symptoms and abnormal lab findings . The goals were rebalancing her glucose levels, stress response and iron levels. I also gave her dietary guidelines and recommended that she focus on getting at least seven hours of sleep per night and add 30 minutes of strength training twice a week to her current exercise routine.

We met monthly over the next 6 months. At times when she plateaued, we revisited her treatment plan and made sure she was on the right track. Fast-forward to a few months later, we re-tested the abnormal markers, and it showed reduced fasting insulin level and improved thyroid function (normal TSH level).

She reported she felt much more like her old self and even lost some weight. She also mentioned her food cravings were reduced, even when she felt stressed. She admitted later that previous to our work together she was using food for comfort. 

It was not an overnight success. After  the course of 6 months, she continued to follow her plan and over time, was able to lose the weight she wanted and keep it off.

Chronic fatigue, stress and insulin resistance are often interrelated. You cannot change what you don’t measure. The best way to make progress is to work with a trained healthcare provider to help learn what is off balance in your body and address them together. It is not fast medicine, but your health is well worth the investment.