Felice Jacka, a leading researcher of nutritional psychiatry, has found links between ultra-processed foods and the health of our brains. She explains that our gut microbiome affects various aspects of health, including metabolism, blood glucose, body weight, gene expression, serotonin levels, stress response, mitochondrial function, and immune system. Jacka's research has shown that a western junk food diet can impair cognitive functions and shrink the hippocampus, a brain region important for mental health, learning, and memory. The industrialized food system, which produces ultra-processed foods, is the leading cause of illness, early death, and biodiversity loss globally, costing around $20tn per year. Jacka suggests that reducing consumption of ultra-processed foods is crucial, but acknowledges that many people don't have the option due to their affordability and the lack of healthy choices available. She has also found a connection between ultra-processed foods, poor diet quality in mothers and children, and neurodevelopmental disorders such as ADHD. Jacka acknowledges that the term "ultra-processed food" may have some fuzzy borders and misclassifications, but warns against industry tactics to confuse people and muddy the waters, similar to what the tobacco industry did with smoking and lung cancer.
Population-based studies conducted in several countries, most of them using national dietary intake surveys, have shown that ultra-processed foods are typically high-energy-dense products, high in sugar, unhealthy fats and salt, and low in dietary fibre, protein, vitamins and minerals
Because it starts off saying
A practical way to identify an ultra-processed product is to check to see if its list of ingredients contains at least one item characteristic of the NOVA ultra-processed food group, which is to say, either food substances never or rarely used in kitchens (such as high-fructose corn syrup, hydrogenated or interesterified oils, and hydrolysed proteins), or classes of additives designed to make the final product palatable or more appealing (such as flavours, flavour enhancers, colours, emulsifiers, emulsifying salts, sweeteners, thickeners, and anti-foaming, bulking, carbonating, foaming, gelling and glazing agents).
Which like, could be literally anything, but adding the whole "they tend to be high in sugar, fats, and salt, while being low in fibre and nutrition" makes it make a lot more sense. It's not that the additives themselves are necessarily bad, but rather that they're making up for a lack of real substance. You don't get the nutrition you need and parts of your body atrophies, seems logical.
MSG is fantastic and can bring an already good dish to a new level, or you could add a whole lot of it into a bad dish and possibly elevate it to palatable.