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The Four Metabolism Killers

The Four Metabolism Killers


Metabolism denotes all the chemical processes that take place in your body, and  each process requires energy.  The amount of energy that is required to run all these chemical processes, even while you are at rest, is known as Basal Metabolic Rate (1). There are several factors that affect your Basal Metabolic Rate and overall metabolism;  genetics, weight, muscle mass, environmental factors, hormones, lifestyle factors, exercise, diet, and gut health (2) (3) (4) (5) (6) (7) (8). 


Metabolism typically slows after the age of 35, but not because you are getting older.  Your Metabolism is slowing because of the four metabolism killers:


1) Stress: 

Stress affects your body in several ways and can manifest as a headache, abdominal pain, fatigue, body aches, sleep disturbance, changes in appetite, immunity issues, weight gain, cardiac issues, psychological issues such as depression and anxiety, skin issues, and fertility issues (9) (10) (11) (12) (13). 

Effect of stress on metabolism: We humans are a complex machine of bones, muscles, nerve synapses, and chemical hormones. Stress triggers a sequence of events that opens a Pandora's Box of symptoms and consequences. When you are exposed to stress for a short time, an acute stress event, your brain will go into "Fight or Flight response". Brain will signal your systems to get ready for a fight and will execute the physiological functions for that. Simply put, acute stress triggers the release of cortisol from the adrenal glands (a gland present on the kidneys). Cortisol stimulates the release and production of glucose, slows down digestive system, regulates immunity, and slows down growth. The effect of cortisol along with the adrenaline can help us go through the acute stress event (14) (15) (16) (17). 

Chronic stress can lead to prolonged release of glucocorticoids (a steroid hormone released by the adrenal gland) and Neuropeptie Y (an amino acid that works in the brain). Prolonged and excessive release of cortisol can cause a sequence of events leading to slowing your metabolism, decreasing your BMR, and causing weight gain, obesity, diabetes, hypertension, cardiac issues, PCOS, and metabolic syndrome (18) (19). Cortisol stimulates the release of glucose into the blood, changes the metabolism of protein and fats causing muscle loss, and increasing lipid levels in blood, alters immunity exacerbating autoimmune disorders and allergies, and so many other health problems. Chronic excessive release of cortisol leads to decreased insulin sensitivity leading to "Insulin Resistance" (20). Insulin resistance is associated with weight gain, obesity, PCOS, and other metabolic disorders (21).

2) Sedentary Lifestyles: 

A Sedentary lifestyle is associated with health problems such as obesity, Diabetes, mental health issues, osteoporosis, increased cholesterol levels, cognitive impairment, and increases your chances of developing cancer (23). 

Effect of sedentary lifestyle on metabolism: A sedentary lifestyle is disastrous for your metabolism: Your muscles are doing minimal work, only essential activities like breathing and circulation are taking place in your body, your muscles will uptake and use limited glucose, leading to conversion of excess glucose to fats. The fat produced will accumulate in your body and your blood vessels, increasing your risk of developing heart problems and stroke (24) (25). 

3) Poor Diet:

You need a balanced diet that includes  carbohydrates, proteins, fats, minerals, vitamins, and fiber of optimal calories to maintain a healthy metabolism and your overall health.  Any diet deviating from this is considered a poor diet and puts you at risk of not digesting micro and macro nutrients essential to your body  (26). Poor diet includes both under eating, over eating, and diet lacking essential nutrients. Poor diet can lead to fatigue, osteoporosis, vitamin deficiencies, anemia, mental health issues, diabetes, hypertension, cancer, and stroke (27). 

Effect of poor diet on metabolism:

The most common type of poor diet that goes unnoticed or not taken seriously is a diet containing processed foods.  They are high in refined sugars, refined carbohydrates, high in saturated fats and Trans fats, and low in protein and fiber (28). These types of foods are easier to digest since they are simple carbohydrates devoid of protein and fiber. It will spike your blood glucose levels quickly, and your body is spending only minimal amount of energy to digest this food. The excess amount of calories, which are sugars will be converted into fats and accumulated in your body (29). It will disturb the neuro-endocrine pathway of hormones such as Leptin and Ghrelin, and will not make you feel full even after having food. In the long term, it will lead to insulin resistance, which can in turn cause diabetes, obesity, PCOS, Hypercholesterolemia (increased cholesterol levels in blood), and metabolic syndrome (30).

4) Fad Diets:

Fad diets are highly advertised diets that are famous for a short time and are promised to cause drastic weight loss in a short time (31). Most of these diets claim to have scientific evidence of its efficiency, but often lack the scientific basis. Some of the Fad diets are the egg diet, carnivore diet, soup diet, lemon detox, cabbage diet, water diet, juice cleanse, fruit diet, raw vegetable diet, and many others (31) (32). These diets offer quick results due to dehydration or severe calorie restriction, but this restriction will cause you to reach a plateau.  And since significant calorie restriction is not sustainable in the long term, you will rapidly regain weight once you eat a normal amount of calories (32). Fad diets can also cause headaches, vitamin deficiencies, and kidney stones, (33)

Effect of fad diets on metabolism: 

Your body needs all nutrients in balance to function effectively and going without any essential nutrient or mineral will damage your metabolism (35). Most of the Fad diets cause similar results associated with nutrition deficiencies and metabolic damage. 


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