The Medicine Cabinet Within: Why Am I Always So Tired?

Many patients show up at our clinic frustrated with the feeling that despite their best efforts to take care of themselves, they never have the energy they want to get through the day. Many say they are eating well and exercising yet still feel tired most of the time. Low energy levels and persistent fatigue are quite common, and the explanation for it can vary greatly. There is a wide range of underlying causes to explore and rule out, ranging from outright measurable physiologic causes to issues that may be more multifactorial, and hard to pin down.

It’s important to point out that the feeling of fatigue is subjective and individual — for some, deficits in energy are fleeting and inconsistent, while for others it is so persistent and debilitating that it warrants a diagnosis of chronic fatigue syndrome. This syndrome includes severe fatigue that truly limits daily activity and is worsened by any exertion. Fatigue of this degree is often not relieved by sleep, is accompanied by cognitive issues and may even include physical pain. In these instances, chronic infections or environmental exposures may be contributing and warrant an extensive specialist work-up.

Wherever someone lands on the energy spectrum, the starting point should be a thorough work-up with a health care provider who is willing to take the deep dive. The first step should be ruling out some of the most well-known metabolic causes of fatigue.

Red blood cell anemias, most typically caused by either iron deficiency or vitamin B12 deficiency, are a notorious cause of persistent fatigue and are easy to identify on lab work. If RBCs are too small (may be iron deficiency) or too big (B12 deficiency) they are inefficient at delivering oxygen to every cell in the body. If this exchange of oxygen and carbon dioxide is compromised in our bodies, fatigue is inevitable. Be sure your provider runs a ferritin level on labs as well, as this can be a “hidden” clue to what is going on beneath the surface regarding the body’s ability to produce a healthy red blood cell.

The endocrine system and its hormone levels are an area of metabolism that is also important to explore for concerns of fatigue. Low thyroid function (hypothyroidism) is at the top of the list of medical causes and is very identifiable in lab work. Additionally, there is a relationship between thyroid function, adrenal function, cortisol, insulin and blood sugar levels that gets a bit more complex and is worth exploring with a holistically oriented medical provider. In some cases, thyroid hormone levels are fine, while the daily rhythm of adrenal function and associated hormones may be taxed and out of balance, causing fluctuations of cortisol, insulin and blood sugar that will contribute to fatigue. This phenomenon becomes a place where the endocrine system meets lifestyle, how we are eating and sleeping, as well as stress levels. In these instances, the solutions may include beneficial supplements but commonly require new levels of self-care and upgrades in lifestyle or diet, in order to tap into the ever-present “medicine cabinet within” for healing and improvement in energy levels.

Sleep might be worth mentioning here, as roughly a third of Americans report getting less than the recommended minimum of seven hours of sleep nightly, while up to 20% of adults report difficulty falling or staying sleep, and up to half of adults report not feeling at all refreshed upon waking in the morning. The vast majority of this could be addressed with the very grandmotherly advice of “Go to bed earlier, turn off your phone and TV by 9pm, go for a walk after dinner and spend five minutes writing in a journal before bed to get those thoughts out of your head.” Thanks Grandma, because these really do help, but in some cases there are also very real medical issues of sleep apnea/nighttime hypoxia that need to be addressed to allow for truly rejuvenating sleep, which is absolutely crucial for energy the next day.

While this discussion is far from comprehensive for issues causing persistent fatigue, it does address some of the most common reasons. Often the combination of honest reflection of one’s lifestyle and diet alongside a thorough medical work-up will help one turn the corner toward greater energy and vitality.

–Joshua Phillips, ND is a naturopathic physician and the director at Hawthorn Healing Arts Center in Bend, Oregon. He can be reached at docnaturecure@gmail.com with questions or comments.

This article appears in the Source September 17, 2026.