Mental & Physical Health: A Deeply Interconnected Relationship

Jun 13, 2022 | Blog, Anxiety, Depression, Mental Health, Stress

Formerly considered two entirely separate entities, research is now showing us that the link between mental and physical health is incredibly significant. There are countless associations between the two that involve factors such as our immune system, our diet and exercise routine, our spirituality, and even our gut microbiome. The World Health Organization refers to overall health as a state of complete physical, mental and social well-being. Understanding the deeply complex relationship between mental and physical health can allow us to improve our well-being and ensure that we are truly healthy people.

Gut-Brain Axis

The gut-brain axis is the relationship that exists between both the gut and our neurological systems (Holingue, 2020). Gut health has become relatively trendy as of late, and for good reason. Research has highlighted how crucial gut health is for overall well-being but especially so for mental health. Many mood disorders such as anxiety and depression as well as autism spectrum disorder are linked directly to GI disruptions (Appleton, 2018). Certain bacteria that reside inside the gut are the cause of such a link. Much of the bacteria that exist in our guts are derived from the foods we eat. For this reason, it is more important than ever to choose high-quality, nutrient-dense foods. By creating a diet full of nutrient-dense foods, we can diversify the gut bacteria that exist in our system. When our microbiome is diverse, we are better equipped to fight diseases of both the body and mind.

Immune System

Another commonly misunderstood association exists between our immune system and our mental health. Traditionally, the immune system has been viewed as a direct reflection of physical health but now we understand that the brain has significant involvement as well. The well-being of our minds exerts a massive impact on our physical system, including our immune system. Those suffering from psychiatric diseases often experience immune system suffering as a result of these diseases (Bennett 2019). This can again be tied back to the gut-brain axis as we know our gut health is linked to our immune system function as well.

Exercise, Diet, and Sleep

One of the most obvious and long-understood relationships that exist between the mental and physical health of a person is rooted in their exercise and diet routine. When suffering from a mental illness, diet and exercise are dramatically impacted as a loss of motivation or appetite is experienced. In contrast, many suffering from illnesses such as depression can experience binge eating as well. While the modality differs, the common experience is a lack of adequate nutrition and physical movement. When this occurs, we can see significant weight gain or weight loss, weakened immune systems, lack of essential vitamins such as vitamin D which is known for its mood-regulating abilities, and even high blood pressure. The effects on physical and mental health are equally damaging. 

Another pillar of proper mental and physical health that has a direct relationship with diet and exercise is sleep. Quality sleep is essential for healthy humans and sleep quality is increased by adequate exercise and nutrition. In a study performed using rats, those deprived of REM sleep had a lifespan of 5 weeks compared to 2-3 years for those that did experience regular REM. Improper diet and use of substances like alcohol deprive the body of REM sleep. In contrast, the amount of REM we experience is increased when we get proper nutrition and vitamins in our diets and engage in frequent exercise of at least one hour per day. For this reason, it is absolutely vital that we are conscious of what we are putting into our bodies. In order to promote the highest level of whole-body well-being, a proper diet and exercise routine is crucial to maintain.

Physical Manifestation

Stress, anxiety, and depression are just a few of the mental health conditions that are proven to manifest in physical symptom forms as well. A lack of appetite, digestive issues, headaches, and jaw tension are some of the more commonly experienced symptoms that may occur. A study performed in Canada showed that citizens that report suffering from depression also experience up to three times as many chronic physical conditions as the general population. Mental illness and psychiatric disease can wreak havoc on the body and has the ability to disrupt the entire system. Poor digestion, chronic pain, and discomfort are just a few of the many ways symptoms can manifest on a physical level.

Substance Abuse

Addiction to or abuse of substances such as alcohol, cigarettes, or drugs is viewed as primarily a mental illness. While this is rooted in truth, there is a complex relationship that exists between the two. For example, suffering from a chronic physical illness may be a driving force for addiction. As people use addictive substances as a coping mechanism to reduce discomfort, they are significantly more likely to become actively addicted. An example can be seen in those experiencing depression. Approximately 33% of people suffering from major depression also have a co-occurring addiction. This form of self-medicating has major implications for both physical and mental health. Increased risk of cancer, heart disease, and lung disease are just a few of the many dangers that result from addiction. Substance abuse can be caused by either a mental or physical illness and as a result, we are seeing a consistent increase in those affected from year to year.


The role of spirituality has been linked to improved mental and physical health through meditation, religious practices, yoga, and grounding in nature. Some of the common improvements seen in those practicing spirituality are decreased anxiety and depression, improved physical abilities, a decrease in chronic pain, and even greater odds when fighting cancer. A study that observed cancer patients found that their religious practices and/or spirituality increased their physical health (Jim 2015). In fact, the link was significant enough for researchers to conclude that patients’ religious and spiritual needs are a vital part of comprehensive cancer care. 

Meditation is another aspect of spirituality that has had major implications on mental and physical health. Some of the benefits of this practice are lower blood pressure, improved mood, lowered cortisol, reduced memory loss, and an even greater ability to fight addiction (Khusid 2016). Harnessing spirituality is one of the lesser-known strategies to improve mental and physical health but has been consistently proven as highly effective for both.

The link between mental and physical health is one that is complex in nature. The two are constantly interacting and playing crucial roles in all major body functions. Excellent physical health cannot exist when one’s mental health is poor and vice versa. It is increasingly important to take care of both the body and the mind to increase longevity and quality of life. Gut health, immune health, spirituality, and diet are some of the many avenues through which we can promote healthier bodies and minds. Using a holistic view of the body’s systems is beneficial for understanding how each respective part of the human body is vital for overall wellness.

New Dimensions Can Help!

If you or someone you know is experiencing any of the above symptoms or problems, New Dimensions can help. Our team of experienced therapists and psychiatrists can help you overcome these challenges and help you develop the skills you need to thrive. To schedule a complementary assessment or to find out more about our programs, contact us at 1-800-685-9796.

Our affiliate, MHThrive, provides Individual Therapy, Couples and Marriage Counseling, and Family Therapy at our locations in Katy, The Woodlands, and the Clear Lake area of Houston, Texas. We also provide telehealth therapy for anyone who resides within the State of Texas. To schedule an appointment with one of the MHThrive therapists, contact us at 713-477-0333 or visit to learn more.