A new study published in the American Journal of Clinical Nutrition has been able to link food with a higher glycemic index to making people depressed. James E. Gangwisch, an assistant professor at Columbia University in Psychiatry, wanted to find out whether foods with a higher glycemic index (GI) would come hand in hand with increased rate of depression. A glycemic index is a chart that ranks carbohydrates in foods by how much it raises blood sugar. Gangwisch says his curiosity for this question goes back to when he was a kid and a “candy junkie”. He states, “I noticed for myself, if I eat a lot of sugar, it makes me feel down the next day.” So he decided to test whether a junk food diet could lead to people becoming depressed.
He decided to use data from food questionnaires and a scale that measures postmenopausal women depressive disorders. We have to keep in mind that he has designed an observational study that could suffer from chance and other variables. The data came from about 70,000 women, none suffering from depression at the start. They also had a follow up 3 years after the studies start.
They found that diets that were higher on the glycemic index were associated with increased risk of depression. This includes foods with refined grains and added sugar. On the otherhand, the researchers also found that certain food types can have protective qualties when it comes to developing depression. Foods containg things such as fiber, whole grains, whole fruits, vegetables and lactose all help protect the body from developing depression. All these types of foods normally have a very low glycemic index. Also they say sugars in it self isn’t bad, like total sugar or total carbohydrates, but added sugars are associated with depression.
Now what mechanisms are behind this assocation with depression? They could not pinpoint one but they think one possibility is that the overconsumption of these refinded sugars and starches can cause inflammation and cardiovascualar disease. They say both of these have been linked to the development of depression. They also noted that this high glycemic index diet could lead to insulin resistance, which has been linked to cognivitve deficits that have been found in people with major depression.
This study is far from being complete and only shows a correlation, which isn’t causation. More research is needed on this subject and they don’t know if the results would be the same for different groups of people such as men and younger adults. Gangwisch still believes having a low glycemic index diet is worth it. He states, “I think it’s important and I think it has a big effect on your mood and how you feel and your energy level.” So take this study with a grain of salt because not enough research is out on this subject, but there is a possible link between junk food and depression and you might want to change your diet to a healthier one.
I find it interesting in the GI chart how foods like watermelon, pineapple, dates, onions and beets, all of which are known to be relatively healthy, have near-high or very high GI indexes. These fruits and vegetables are not ones that I would ever advise people to stay away from, given their health benefits, even if this chart claims they have a high GI index. So, does this maybe pose as an exception from harmful GI indexes? That being said, everything should be eaten in moderation so I guess if someone were to eat an excessive amount of dates or onions, that may not end up being beneficial for their diet. It makes sense that poor eating habits lead to depression. Obesity may very well serve as a mechanism between the two because poorly maintained diets are likely to lead to unwanted weight gain which, in turn, has been proven in many cases to lead to depression. The idea that eating a “well-balanced diet leads to a healthier and happier lifestyle” rings true in the case of these studies of your blog post.
As someone who also always feel down whenever I consume junk food, I can personally relate to this blog. Although it seems like there has been research conducted that finds a link between junk food and depression, there definitely isn’t enough research to completely back it up. I think a larger group of people needs to be used in the research, including children and men. Additionally, depression is a disease that can form from anyone, so it’s unknown if it just so happens to be chance that these people who consume food higher in sugars and fat become depressed. TIME magazine wrote an article also explaining the link between junk food and depression which seems promising: http://time.com/3939974/sugar-junk-food-depression/