The Science Behind Stress and it’s Impact on Weight Loss and Overall Health

According to a recent study, about 25% of Americans say they’re dealing with high levels of stress and another 50% say their stress is moderate. Stress occurs when the body encounters changes or challenges – it can be both physical and emotional.  While some stress is normal i.e., keeps us alert, motivated and ready to avoid harm, prolonged stress is extremely harmful to our overall wellbeing.

What happens to our body when we are stressed?

When our body is faced with a challenge/stressor, or even just a change, the hypothalamus kicks into gear and sends out stress hormones. These hormones are controlled by the Sympathetic Nervous System and stimulate the body’s “fight or flight” response. The Adrenal glands release adrenaline (epinephrine) and the body responds accordingly:

• Muscles tense, providing protection from injury
• Heart beats harder and faster and distributes oxygen-rich blood quickly to the brain, muscles, and vital organs
• Majority of blood vessels constrict diverting more oxygen to muscles (raises blood pressure)
• Liver produces more blood sugar providing added and instant energy
• Digestion slows or even stops, allowing the body to focus on the perceived threat

Once the perceived challenge/stressor is gone, the body should switch back to using the Parasympathetic Nervous System (rest and digest). The muscles will relax, breathing will slow/regulate, blood pressure will return to normal; the body will absorb any leftover blood sugar, and digestion will resume.

What happens when stress is chronic?

When the body is faced with chronic stress, it struggles to enter recovery mode (rest and digest). Over time, this constant state of stress creates wear and tear on the body.

• Cortisol stays elevated. Over exposure to cortisol can lead to thyroid problems and cause excess abdominal fat.
• Muscles stay tensed resulting in tension headaches and chronic pain.
• Heart rate and blood pressure stay elevated resulting in increased risk of heart attack, stroke, and hypertension.
• Excess blood sugar is produced increasing the risk of developing type 2 diabetes.
• Continued delay of emptying of the stomach often leads to stomach aches, indigestion, bloating, and an imbalance of gut bacteria.

Can chronic stress affect weight?

The answer is yes. Unfortunately, there is no rule of thumb for when acute stress becomes chronic stress.

1 – ELEVATED CORTISOL

Repeated elevation of cortisol can lead to weight gain and specifically visceral fat storage, often called “belly fat”. Cortisol can mobilize triglycerides from storage and relocate them to visceral fat cells, those under the muscle, deep in the abdomen. The biochemical process at the cellular level has to do with an enzyme control which converts cortisone to cortisol in adipose tissue. More of these enzymes in the visceral fat cells may mean greater amounts of cortisol produced at the tissue level, adding insult to injury, since the adrenals are already pumping out cortisol. Also, visceral fat cells have more cortisol receptors than subcutaneous fat.

A second way cortisol affects weight gain is through the blood sugar and insulin connection. Consistently high blood glucose levels, along with insulin suppression, lead to cells that are depleted of glucose. These cells will continue to look for energy, sending hunger signals to the brain. This can lead to overeating. Unused glucose is also stored as body fat.

Another connection is cortisol’s effect on appetite and especially cravings for high-calorie foods i.e., stress eating. Studies have shown a direct correlation between cortisol levels and calorie intake especially in women. Cortisol directly influences appetite and cravings by binding to hypothalamus receptors in the brain. Cortisol also indirectly influences appetite by modulating other hormones and stress responsive factors known to stimulate appetite.

2 – GASTROINTESTINAL PROBLEMS

Cortisol activates the sympathetic nervous system, causing all the physiologic responses previously described. This means that the parasympathetic nervous system is suppressed, since the two systems cannot operate simultaneously. The parasympathetic nervous system is stimulated during quiet activities such as eating. For the body to best use food energy, enzymes and hormones controlling digestion and absorption must be working at their peak performance.

In a cortisol-flooded, stressed-out body, digestion and absorption are compromised when food is consumed. Ulcers are also more common during stressful times, and many people with irritable bowel syndrome and colitis see improvement in their symptoms when they mitigate stress.  Mucosal inflammation also leads to the increased production of cortisol, and the cycle continues as the body becomes increasingly burdened.

How to Prevent Future Health Issues

Although decreasing your stress levels may seem impossible, you can still manage the effects of elevated cortisol. Practicing relaxation through mindfulness, meditation, yoga, or deep breathing can help bring levels back to normal. If those don’t work, try doing a puzzle, crossword, or even paint-by-number.

You can also help prevent the excess storage of empty calories by consuming a healthy diet. Even though your body may crave a quick fix, do your best to stick with a routine of healthy, nutritious foods. It might not always be easy, but it’s worth it. By watching your food choices, the calories you consume will be turned into energy, not converted into fat, and stored by the body.

Finally, exercise is a great way to manage stress hormones. Whether you go for a run, take a daily walk with your family, or hit the gym, exercising will help maintain your lean body mass.