Conversely, an inadequate diet can lead to fatigue, impaired decision-making, and can slow down reaction time. In fact, a poor diet can actually aggravate, and may even lead to, stress and depression.
Hunger affects your mental health
Facing hunger can be stressful. Constantly worrying about where your next meal will come from can cause mental health problems such as depression, anxiety, and even posttraumatic stress disorder (PTSD).
There are many contributing factors to depression, but did you know that poor nutrition can also play a role? In fact, recent studies by Harvard Medical School concluded a clear connection between a poor diet and an increased risk of depression.
But for most people used to regular meals, skipping meals causes a drop in the body's blood sugar levels. If prolonged, this drop may lead to increased feelings of anxiety and irritability. Other anxiety-provoking effects of low blood sugar are dizziness, light-headedness, confusion and weakness.
Emotional and Cognitive changes: Depression, anxiety, irritability, increased mood fluctuations, intense and negative emotional reactions, decreased enthusiasm, reduced motivation, impaired concentration, problem solving and comprehension, increased rigidity, obsessional thinking and reduced alertness.
It has been shown that your body temperature lowers when you don't consume enough calories. You feel lethargic. Without enough calories, you will quickly experience feelings of fatigue. Because your body doesn't have enough calories to burn and generate energy.
Mood is badly affected by under-eating. Under eaters generally feel depressed, low, and prone to be easily irritated or enraged. Panic attacks are a very common side-effect of undereating and are only likely to subside when you recover back to a healthier body weight.
When you stick to a diet of nutrient-rich foods, you're setting yourself up for fewer mood swings and an improved ability to focus. Studies have even found that clean diets consisting of mainly whole, unprocessed foods, can help with symptoms of depression and anxiety.
If a person continues not to eat, they can have slurred speech, confusion, syncope (fainting), or seizures. Prolonged lack of nutrition can lead to severe weight loss, fatigue, depression, and stomach issues.
Brain Recovery After Anorexia
Parents of patients with anorexia report a range of time, from six months to two-plus years for full “brain healing” to occur.
All of these symptoms can be related to mental health conditions including depression, bipolar disorder, ADHD, or other conditions. These symptoms can be seen with Alzheimer's disease and other forms of dementia as well.
Some markers include reduction in blood pressure and cholesterol levels, and surprisingly an increase of energy and clarity of thinking. One theory is that hunger initiates a constant stress level that makes us stronger and more resistant to aging.
The biology of being hangry
“When you haven't eaten for a while, the level of sugar (glucose) in your blood decreases,” she explains. When your blood sugar gets too low, it triggers a cascade of hormones, including cortisol (a stress hormone) and adrenaline (the fight-or-flight hormone).
It seems "hangry" isn't just a made-up term. University of Guelph researchers have revealed that the sudden drop in glucose we experience when we are hungry can impact our mood. "We found evidence that a change in glucose level can have a lasting effect on mood," said Prof. Francesco Leri, Department of Psychology.
One of the most common signs of depression is a change in how much you eat. For some people with depression, this means a loss of appetite, while for others, the amount you eat may increase. "Loss of appetite can be an early sign of depression or a warning of a depression relapse.
For most people, there are no serious dangers involved in eating one meal a day, other than the discomforts of feeling hungry. That said, there are some risks for people with cardiovascular disease or diabetes. Eating one meal a day can increase your blood pressure and cholesterol.
When a person has been eating a low-calorie diet for long enough to actually be starving—there's no specific caloric threshold or length of time for this to happen because it's so individual, the experts explain, but it certainly takes longer than a day without food—a few physiological processes take place.
After 14 Days
This is what may ultimately lead to death. Because a starving body lacks the resources to stay healthy, infection is another possible cause of death.
Mental exhaustion is a feeling of extreme tiredness, characterized by other feelings including apathy, cynicism, and irritability. You may be mentally exhausted if you've recently undergone long-term stress, find it hard to focus on tasks, or lack interest in activities you usually enjoy.