Here are some of the common signs of a slow metabolism: • Continual fatigue - slow metabolism can leave you feeling tired all the time, even when you have had a good night’s sleep. • Continuous headache - slow metabolism can cause frequent headaches, including severe migraines, and sudden onsets of pain. This is related to malfunctioning thyroid glands. • Weight gain - slow metabolism can lead to weight gain for no obvious reason, this is most likely related to hypothyroidism. Weight gain can happen even when you eat right and exercise when you have a slow metabolism. • Constipation - slow metabolism slows the processing of food for energy, which results in constipation. • Depression - slow metabolism affects your gut and can have an impact on your mind and your mood. • Dry skin, thin hair, and brittle nails - people with a slow metabolism tend to have low thyroid hormone levels which cause issues with the skin, hair, and nails.