The negative effects of sugar on the body, from obesity to tooth decay, are well-known. Recent medical research is also showing stronger links between sugar consumption and symptoms of depression and anxiety.
Because sugary foods are widespread and popular, understanding this connection is important to maintaining good mental health.
Keep reading to learn more about the links between sugar and depression, including the latest research on how sugar can affect mood and emotion and how a person can control their sugar intake.
Although added sugar can lead to an imbalance of insulin and blood sugar, refined carbohydrates and sugars also drain the B vitamins required to sustain a positive mood.
This can also affect a person’s thyroid, with thyroid hormones regulating body temperature, metabolism, and growth. These factors may all impact a person’s mindset.
Sugar is a carbohydrate molecule, and there are two types.
The first is called simple sugar, and it is present in fruits, vegetables, nuts, whole grains, and beans. Because these foods contain vitamins, proteins, and fiber, they slow down sugar absorption and make it a healthful option.
The second is added, or processed, sugar, which has no nutritional value. Added sugar is present in candy bars and soft drinks, among other foods and beverages. The body does not absorb this kind of sugar, so the sugar goes straight into the system.
Although research is ongoing, people with a very high sugar intake are more likely to experience symptoms of depression.
Glucose, or blood sugar, is the simplest of the carbohydrates. It is also essential for human survival. Glucose acts as the primary source of energy for every cell in the body, and the brain depends on it. An even supply of glucose keeps the brain functioning in a balanced way.
However, consuming too much added sugar may lead to increased irritability and peaks and drops in energy levels. Although the initial intake of sugar may feel positive, it will cause blood glucose levels to drop. It is this that affects the mind and body so dramatically.
For some people, however, sugar can be incredibly addictive. When a person consumes sugar, the mesolimbic dopamine system in the brain offers a reward, thereby increasing mood. The dopamine system starts working when feelings of pleasure approach.
Because these are added sugars, however, they are not beneficial to the body in any way. A high intake of these will mean chemical changes in the body. These occur to prevent overstimulation, so the body may crave more sugar on future occasions to achieve the same high mood.
Diabetes and depression
The connection between diabetes and depression provides an illustration of the glucose effect on depression. According to Diabetes UK, people with diabetes are twice as likely to experience symptoms of depression.
Eating regularly is vital for some people with diabetes. However, it is important that they choose food options that will balance their sugar levels and release energy slowly.
High blood sugar levels can make people with diabetes feel:
One of the major links between sugar and depression is systemic inflammation.
One study looked specifically at added dietary sugars. It found that elevated systemic inflammation is a potent physiological trigger of depression.
Inflammation is also connected to other depressive symptoms, such as changes in appetite, sleep deprivation, and fatigue. The above study also examined potential inflammation in the brain and found that excessive sugar consumption could affect its reward system.
Several studies have linked added sugar with chronic inflammation. Although depression is not an inflammatory condition, increased inflammation does occur in other psychiatric conditions. These include schizophrenia, bipolar disorder, and anxiety.
Another study found that inflammation is often a factor in cases of depression. Emotional stress can also lead to inflammation in the brain.
The National Institute of Mental Health report that in 2017, an estimated 17.3 million adults in the United States had at least one major depressive episode. This represents around 7.1% of all U.S. adults.
In the same year, around 264 million people had depression worldwide.
Although global research into the link between sugar and depression continues, many studies continue to demonstrate that high levels of sugar may contribute to poor mental health.
It can be difficult to reduce sugar intake, but there are certain things a person can try.
The sections below will discuss these in more detail.
Avoid processed foods
Healthful food is not only good for the digestive system. It also keeps the stomach full for longer and helps the brain function more effectively.
However, processed foods with added sugar can only provide a short-term high. Processed foods may also have hidden amounts of sodium.
Although candy and ice-cream are some obvious sources of added sugar, bread, cereal, milk, and cheese are also processed foods that can further increase intake.
Control sugar consumption
Although the addictive properties of sugar are well-known, it should now be easier than ever to control consumption.
As recently as last year, the Food and Drug Administration (FDA) announced new guidance for food and drink labeling around added sugars. Nutrition labels previously put sugars into one category.
However, some other common names for sugar include:
- high-fructose corn syrup
- castor sugar
- fruit juice
The American Heart Association (AHA) recommend around 6 teaspoons of sugar per day for women (100 calories) and 9 teaspoons per day for men (150 calories).
To put that into perspective, one can of Coca-Cola contains around 8.25 teaspoons of sugar.
Avoid adding sugar to hot beverages
Adding a few teaspoons of sugar to a cup of tea or coffee might also negatively affect mood. In fact, some research found that participants who consumed more sugar-sweetened beverages had a higher chance of experiencing symptoms of depression.
The average person in the U.S. consumes around 22 teaspoons worth of added sugars every day.
Sugar can be very addictive, as the dopamine that the brain releases when a person eats sugar provides a high, which can become a dependence.
However, many people who completely eliminate sugar from the diet find themselves irritable, moody, and with low energy. Moderation could be key.
As more and more studies find links between sugar and depression, it is important to be aware of the dangers of added sugar.
Although clearer labeling is helping, the best option is to look toward the fruit and vegetable aisles when shopping.
One of the easiest ways to reduce added sugar intake is to avoid soft drinks and not add sugar to tea or coffee. Beverages are generally the biggest contributors of sugar to any diet.
Added sugar rewards the dopamine system in the brain, creating a short-term high. However, there is also a potential physical and mental low from a high sugar intake.