14 common causes of weakness and tiredness

Have you ever had a day where you feel like you have just run out of energy, no matter how much you rest or how many cups of coffee you drink? It is one of those moments when you wonder, Why am I so tired all the time? Well, persistent weakness and tiredness can actually stem from a lot of different things, draining your energy levels and leaving you feeling physically and mentally exhausted. This may include poor lifestyle, nutrient deficiencies, or serious conditions like blood sugar fluctuations, thyroid, stress, etc. Side effects of certain medications could also be one of the common causes of weakness.

14 causes of weakness you should know

Here are some of the common causes of weakness and tiredness:

1. Vitamin B12 deficiency

Vitamin B12 is essential for nerve function and producing red blood cells. If you are deficient, your body cannot function properly, leading to fatigue, weakness, and trouble concentrating. The Journal of Clinical Sleep Medicine links low vitamin B12 levels with tiredness and muscle weakness. Not only this but other nutrient deficiencies, including iron, vitamin D, and magnesium, can also lead to weakness.

2. Electrolyte imbalances

This is one of the most common causes of weakness. Electrolytes such as sodium, potassium, and calcium help regulate muscle and nerve function. If these minerals get out of balance, often due to dehydration or kidney problems, it can cause weakness, muscle cramps, and fatigue.

3. Sleep problems

If you are waking up tired despite getting a full night’s sleep, you might have sleep apnea. This condition causes your breathing to stop and start while you sleep, leading to poor rest. A study in Frontiers in Psychology shows that people with obstructive sleep apnea often experience daytime tiredness, which can leave them feeling weak and foggy.

4. Chronic fatigue syndrome

Chronic fatigue syndrome is more than just feeling tired. It is a condition where you experience extreme, unexplained fatigue that does not improve with rest. The fatigue is often accompanied by muscle pain and trouble concentrating. It can be frustrating but the exact cause remains unclear. It can be one of most the serious causes of weakness.

5. Blood diseases

Anemia occurs when your body does not have enough healthy red blood cells to carry oxygen. This can lead to a constant feeling of fatigue, weakness, dizziness, and even shortness of breath. According to Stat Pearls, anemia is one of the most common causes of weakness and tiredness, especially in women.

6. Infections

Infections, whether viral or bacterial, can cause fatigue and weakness as the body directs energy to fight off the infection. Infections like the flu or even a cold can drain your energy levels, leaving you feeling weak.

7. Ageing

Ageing is one of the most common causes of weakness. As we get older, we naturally experience muscle loss and strength, leading to increased fatigue and weakness. It can lead to a slower metabolism and lower energy levels, making everyday activities feel more tiring.

8. Muscle diseases

Muscle diseases like muscular dystrophy are a group of genetic diseases that cause muscles to weaken over time. This progressive condition can lead to severe fatigue as muscles lose strength. According to StatPearls, muscular dystrophy affects strength and ability to perform basic tasks, often resulting in chronic tiredness.

9. Neurological conditions

Conditions like multiple sclerosis and Parkinson’s disease affect the nervous system, interfering with movement and other functions. These conditions are the common causes of weakness and fatigue, as well as problems with coordination and balance, making you feel more physically drained.

10. Mental health problems

Mental health problems like anxiety and depression are also one of the most common causes of weakness. You might feel exhausted, even after resting. In some cases, antidepressants prescribed for these conditions can also make you feel drowsy or weak, contributing to chronic fatigue.

11. Thyroid conditions

The thyroid gland is responsible for regulating your metabolism. If it is underactive (hypothyroidism), it can cause tiredness, weight gain, weakness, and sensitivity to cold. A slow metabolism means your body does not have the energy it needs to function efficiently, leading to persistent fatigue.

12. Fibromyalgia

Fibromyalgia is a condition that causes widespread pain and tenderness in the muscles and joints. Along with pain, people with fibromyalgia often experience severe fatigue and weakness, even after a good night’s sleep. According to the Oman Medical Journal, this condition can cause physical and cognitive difficulties that can make even simple tasks feel overwhelming.

13. Medications

Certain medications, like sedatives, blood pressure drugs, and especially chemotherapy treatments, can leave you feeling weak and tired. Chemotherapy, for example, can severely impact energy levels and cause long-lasting fatigue, as highlighted in the British Journal of Cancer. This weakness can make it difficult for patients to perform everyday tasks.

14. Chronic diseases

Chronic conditions such as diabetes, heart disease, chronic lung disease, kidney disease, cancer, and arthritis can all lead to long-term fatigue and weakness. These causes of weakness can strain the body, reducing energy levels and making you feel weak. For instance, people with diabetes may experience fluctuating blood sugar levels that lead to tiredness, while cancer patients often report extreme fatigue from the disease or treatments like chemotherapy.

When to see a doctor?

If weakness or fatigue is affecting your daily life, it is a good idea to consult a doctor. While symptoms from a cold or flu usually go away on their own, see a doctor if they persist afterward. If you are already being treated for a condition and experiencing extreme worsening weakness, this might mean you need a change in your treatment plan. Also, if weakness is accompanied by breathing problems, pain, or an irregular heartbeat, make sure to check in with your doctor.