Foods contain nutrients, the nourishing substances that give your body materials and information it needs to function well. Missing out on important nutrients can have a detrimental effect on metabolic processes occurring in your body. In contrast, getting too much food or food that gives your body wrong signals, such as processed foods, can make you overweight and undernourished at the same time. Furthermore, high consumption of unhealthy foods raises your risk of developing diseases such as diabetes, heart disease and arthritis.
Fragile Immune System
Poor nutrition can cause deficiencies in certain micronutrients that help boost your immunity and insufficient intake of macronutrients and energy. Such nutrient deficiencies can turn off immune responses. Because of the impaired immune system, you are more likely to develop infection and illness, which together can aggravate states of malnutrition by decreasing nutrient absorption, encouraging nutrient loss and changing the metabolism of your body.
Wildly Swinging Blood Sugar Levels
Eating a diet that falls short of vital nutrients can upset the mechanisms that manage your sugar levels, leading to hypoglycemia or hyperglycemia. Hypoglycemia means low blood sugar, whereas hyperglycemia signifies high blood sugar. Lack of nutritious foods and skipping meals can result in hypoglycemia. You may experience hypoglycemic symptoms such as headache, excessive sweating, dizziness, depression, fatigue and blurred vision. On the other hand, eating too much food can cause hyperglycemia. Symptoms of hyperglycemia include excessive thirst, high blood glucose, frequent urination and high sugar levels in the urine.
Obesity is not something that happens overnight -- it develops slowly from poor dietary and lifestyle choices. According to the Harvard School of Public Health, studies in teen and adults showed that regular consumption of fast foods leads to weight gain and obesity. Similarly, evidence suggests that foods such as sugar-sweetened beverages and refined grains multiply the risk of weight gain, obesity and diabetes. The Harvard School of Public Health further says that incorporating whole grains, fruits and vegetables into your diet can help maintain a stable weight. This is because their fiber content slows digestion and helps keep hunger at bay.
Deteriorating Mental Health
According to an article in the April-June 2008 issue of “Indian Journal of Psychiatry,” diets of people suffering from mental disorders -- depression, obsessive-compulsive disorder, schizophrenia and bipolar disorder -- lack critical nutrients such as vitamins, minerals and omega-3 fatty acids. The study further states that making poor food choices might contribute to depression, which is characterized by depressed mood, loss of appetite and increased sadness and anxiety. Deficiencies in neurotransmitters -- brain chemicals that transit information from one neuron to another -- such as gamma-aminobutyric acid, noradrenaline, dopamine and serotonin can lead to depression. People with mental illness usually suffer from deficiencies in common nutrients such as B vitamins, minerals, amino acids and omega-3 fatty acids. These nutrients are precursors to neurotransmitters.