Food and Mood. How Are They Related?

Food in general is a strong natural reward to human, and food intake is a complicated process. Reward and satisfaction associated with food consumption can lead to the production of dopamine. As a result, dopamine activates the reward and pleasure in the brain. This positive feeling of gratification is what causes an individual to repeatedly eating a particular food. This behavior can activate the brain reward pathway which eventually overrides signals of satiety and hunger. Thus, it results overeating and morbid obesity. According to many researches, there is a complicated relationship between food, mood and brain signaling in biological factors.

According to Lyman, it is mood and emotions that affecting eating disorders. “Mood is characterized by psychological arousal in the absence of obvious stimuli that can last for several minutes or longer” (Singh, 2014). On the other hand, emotions are short term response to reinforce stimuli. Emotions such as anger and joy have a significant impact on appetite and choice of food. There is a five way model that predicts different aspects of emotional eating, they are food choice, food intake, loss of cognitive controls, food modulating emotions, and emotion-congruent modulating eating (Macht, 2008). The amount of food intake is depending on the state of negative emotions or distress. There is also has a connection between emotional state and addiction. The amount of food, food choice, and meal frequency are affected by sensory and psychological pathways. Theories suggested that the reason people overeat is because they don’t perceive their physiological state, hunger, and satiety. What they see is that overeating reduces emotional discomfort and anxiety. In normal eaters, on the other hand, they alter their food intake and regulate their emotion. Emotional distress has a significant effect on emotional food choice and intake.

Food, mood, and stress have a close relationship. First, stress affects feeding behavior. The amount of food eaten is depending on the types of external or psychological stressors. Chronic stress can increase the consumption of edible and gratifying food which can lead to obesity. On the opposite side, it can also lower appetite which leads to weight loss. According to studies by Pecoraro, intake of palatable food can reduce signs of stress and anxiety. Second, anxiety and depression both affect the choice of food and metabolism. Anxiety and depression are usually the cause of overeating and obesity in humans. The endocrine and metabolic conditions in one individual are exacerbated in major depressions.

Depressed individuals would consume palatable or comfort food to alleviate their negative feelings. Even though comfort food can provide relief the negative emotions and mood states, but it can also lead to obesity due the chronic consumption of calorie rich foods. This can promote vulnerability to depression and anxiety. Findings showed that consumption of high lipid diet for a long period of time can cause negative emotional states, increase stress sensitivity, and modify basal corticosterone levels (Sharma et al., 2012). As a result, negative emotions not only affect food choice and intake but it can also worsen one’s mood. After more research done by Avena et al, it was found that post exposure to high carbohydrate diet then switch back to normal diet, an individual would craving for more sucrose, high fat food, and also showing enhanced anxiety-like behavior. Overall, consumption of high calorie diet can actually exacerbate the stress, which can lead to a continuous repetitive cycles of overeating, weight gain, and depressed mood.

It is the brain that consumes most amount of energy compare to all other parts of the body. The mechanisms that transfer the energy from food to neurons are essential to the control of brain function. The processes that involved in the control of energy in neurons can affect synaptic plasticity, thus, metabolic disorders can influence cognitive processes (Gomez-Pinilla, 2008).

Research has shown that “food directly influence brain neurotransmitter systems which in turn has effects on mood and performance by altering the brain structure, chemistry, and physiology” (Singh, 2014). Food that impact mood include: chocolate, caffeine, omega-3 fatty acids, micronutrients, resistin, and insulin etc. Chocolate promotes pleasant feeling, and results in good mood through serotonin and cannabinoid receptors signaling. Psychoactive chemicals such as andamines are found in chocolates. This chemical stimulates the brain and results in good mood. However, it can also result in negative feelings in some women on weight loss regimes. After eating chocolate, they will feel guilty.

Sensory factors associated with chocolate eating can make someone to crave for more because of the unique taste and feel of chocolate in mouth. Most caffeine is found in coffee or tea form. Caffeine promotes alertness, vigilance, and reaction time but it also increases anxiety. It relieves symptoms like headaches, drowsiness, and fatigue by blocking adenosine receptors. On the other hand, it can cause withdrawal symptoms when discontinued. Omega-3 fatty acids affects neuroticism, mood, and behavior, it also plays a part in mood disorders. “Omega-3 fatty acids in receptor functioning, neurotransmitters levels and monoamine metabolism are all implicated in depression (Parker et al., 2006).” Micronutrients such as thiamine involves emotions, mood states, and cognitive functioning. Consumption of more thiamine containing food can increase well-being, sociability, and overall energy levels.

However, decreased level of thiamine can worsen mood and cognitive functioning. Iron is another important micronutrient an individual must monitor. Iron deficiency is one of the most common nutritional problem worldwide. Insufficient level of iron in the body can cause depression, problems with attention and lethargy, and anemia. Resistin links to depression indirectly, and researchers have not yet discover the pathway. Lastly, insulin plays a role in mood, depression, anxiety, and negative emotion by insulin receptor signaling.

Diet is in conjunction with others aspects of daily living like exercise, plays an important role in cognitive skills in humans (Gomez-Pinilla, 2008). People’s food choice is depending on their culture, religion, and society. Different diets from different countries can trigger mood and metabolic disorders in an individual during obesity. Studies has shown that there is a direct relationship between brain size and access to food, even a slight difference in diet can cause a huge effect on survival and reproduction among humans. For example, Western diet are rich in saturated fat and low in polysaturated and mono-unsaturated fatty acids. This diet can increase the incidents of one person’s depression.

On the other hand, Mediterranean diets tend to reduce depression. Fish is high in omega-3 fatty acids. According to studies done by Gomez-Pinilla, the major depression annual prevalence decreases as the consumption of fish increases. The graph showed that Asians in Taiwan, Korea, and Japan have a lower rate than people in West Germany, Canada, and New Zealand, etc. People in Asian countries have a better access to rivers and seas than people is European countries. Diets that lack omega-3 polyunsaturated fatty acids, also known as PUFA, increases the incidence of depression. Thus, increased PUFA can reduce depression. DHA is one of the most common omega-3 fatty acid found in cell membranes of the brain. DHA involves in brain and body mass ratio. Based on molecular biology study, cognitive function increases as DHA level in the brain increases. The graphs shown that individual with a higher DHA has bigger brain than the ones with lower DHA level.

Not only high fat diets influence mood change but they also cause weight gain, visceral adipose tissue, more build up of fats at the abdominal area, and increased mortality of cardiovascular disease. According to Tsuboi, the building up of adipose tissue at the abdominal area can lead to many complication such as insulin resistance. Leptin is a hormone produced by adipose tissue, found in hypothalamus, cerebral cortex, and hippocampus, which controls the appetite of an individual. Dysfunctional leptin receptors can lead to long-term depression and obesity. Neurological function impairments occur due to increased amount of plasma fatty acids circulating in blood stream enter the brain (Tsuboi et al., 2013). Leptin and insulin receptor signaling were damaged in hypothalamus, which results weight gain and depression in an individual.

Disturbed eating behaviors can be due to psychiatric disorders. Hypercortisolism, anhedonia, hypophagia, and weight loss are all associate with melancholic depression. Characteristics of depression include increased appetite, carbohydrate craving, reduced hypothalamic pituitary adrenal axis (HPA), and weight gain. Serum cortisol level affects depression as well. Glucocorticoids cause many problems in human body. These include: metabolic, endocrine, immune, and behavioral functions. This particular steroid hormone regulate through the receptors in midbrain and limbic circuits. The purpose of glucocorticoids are maintaining energy homeostasis, modulating HPA activity, emotional, and behavioral effects of stress. When an individual is under physiologic stress, HPA axis is activated, releasing glucocorticoids. Thus, this causes increase of insulin, and motivation for palatable food leading to weight gain.

In order to prevent negative emotions and depression, it is important to make a diet plan. There is not any specific diet that can relieve depression but there is still some diets that can help people to stay in a positive mood. Consumption of food high in antioxidants can help prevent cell damage. Free radicals made by the body can cause cell damage, aging, and many other problems in the brain. Although antioxidants cannot stop the production of free radicals, but it can less their destructive effect. Antioxidants are beta-carotene, vitamin C and E. Food that that rich in antioxidants broccoli, cantaloupe, carrots, oranges, potatoes, strawberries, nuts and seeds, etc.

From previous discussions, food high in carbohydrates are not a wise choice to eat. However, “smart” carbs actually have some calming effects. Carbohydrates are associated with mood-boosting brain chemical, serotonin. Low serotonin activity can lead to carb cravings. “Smart” carbs or complex carbs are food that are low in sugar, such as peas, beans, whole grains, fruits, legumes, and vegetables. Simple carbs like cake, chips, and cookies should be avoid. According to studies, protein-rich foods such as turkey, salmon, tuna, chicken, low fat cheese, milk products, and beans boost alertness in an individual. Tryptophan, an amino acid, is found in these items, which can help with the production of serotonin. Consumption of protein can help boost energy and create a clear mind. As mentioned earlier, Mediterranean diet helps reduce depression due to high amount of B Vitamins.

This diets includes legumes, many fruits, dark green vegetables, fish, and low fat dairy products. Low level of selenium also causes poor moods. It is recommended that a consumption of 55 micrograms of selenium is needed in adults each day. Both selenium and omega-3 fatty acids can be found in lean meat, seafood, and low fat dairy products. Based on studies, obese people have a high chance to become depressed or the ones who are depressed can become obese. This is due to the change in immune system and hormones caused by depression. Nutritious diet can help with weight loss which can improve moods. Individuals should try to avoid alcohol and drugs because they interfere with mood, sleep, and motivation. They can also reduce the effectiveness of depression medications. Caffeine should also be cut back or discontinued after noon since it can trigger anxiety and keeps people awake at night.

In conclusion, it’s is very important in controlling what an individual consumes. Depression can cause someone to have constant carb craving and increased appetite. This can eventually lead to obesity, and it can worsen the anxiety and mood in that particular person. In order to control their mood, sugary and high lipid food should be avoided at all times. Food such as salmon. chicken, peas, legumes, fruits, whole grains, and vegetables are rich in proteins, omega-3 fatty acids, and vitamins should be the primary diets. A balanced diet can reduce the incidents of depression and prevent obesity, and it can also promote quality of life.