DEAR DOCTORS: Can you please talk about what makes something count as "junk food"? My diet has been less than stellar during the pandemic, and not only did I gain weight, but I just got the news that I have prediabetes. Specifics about how those kinds of food are bad for your health would help a lot.
DEAR READER: We have often addressed the adverse health effects of eating a diet that is high in fast foods and snack foods. But with high blood sugar, elevated blood pressure, excess weight, surplus abdominal body fat and abnormal blood lipid levels becoming a not-so-silent epidemic here in the United States, your request for a closer look at these foods is timely.
When someone talks about fast food or junk food, they're often referring to what have come to be known as ultra-processed foods. These are foods that have been so radically changed from their original state that they neither look nor taste like the ingredients from which they are made. This is achieved both through how these foods are treated in the cooking and manufacturing process, and with the addition of a range of ingredients not present in the original food -- salt, fats, sugars, colours and preservatives, stabilisers and other additives.
Ultra-processed foods are precisely formulated to tease our palates with just the right blend of sweet, salty and fatty flavours. They keep us reaching for more, and at the same time prevent us from feeling completely satisfied.
In terms of food engineering, this is a remarkable feat. But when it comes to health and well-being, there's a potentially steep cost.
Ultra-processed foods are high in sodium, saturated fats and added sugars, which contribute to a range of health problems. These include an increased risk of Type 2 diabetes, cardiovascular disease, lowered immune response, certain cancers, dementia and early death.
As your own experience has shown, a diet high in these types of foods often leads to weight gain and obesity. The findings from a clinical trial, which were published in the journal Cell Metabolism, found that the study participants eating a diet high in ultra-processed foods routinely took in 500 more calories per day than those assigned to a diet of whole foods.
Another piece of the puzzle is that these types of foods are lacking in the wide range of nutrients needed to keep our bodies functioning well. They are also low in the dietary fibres that keep the beneficial micro-organisms of the gut microbiome fed and happy.
You've taken an important step by recognising the role of highly processed foods in the weight that you have gained. And a diagnosis of prediabetes, which is blood sugar that is higher than normal, is a wake-up call. It means that you don't have Type 2 diabetes yet, but without lifestyle changes, you are now at increased risk.
Our inbox shows you're far from alone in your wish to ditch junk food and improve your diet. With that in mind, we will follow up soon with a column that explores strategies for success. Universal Features Syndicate
Dr Eve Glazier is an internist and associate professor of medicine at UCLA Health. Dr Elizabeth Ko is an internist and assistant professor of medicine at UCLA Health.