Can UPFs Cause Metabolic Syndrome
Definition - Metabolic Syndrome
Metabolic syndrome is a cluster of conditions that occur together, increasing your risk of heart disease, stroke, type 2 diabetes, and other serious health problems, and is typically characterised by high blood pressure (hypertension), high blood glucose and high blood lipids (dyslipidaemia: elevated triglycerides and LDL and low HDL cholesterol). These conditions are interrelated and share underlying mediators, mechanisms and pathways.[1]
Metabolic syndrome is also called insulin resistance syndrome.
As the definition implies, metabolic syndrome is preventable and rectifiable with simple dietary and lifestyle changes.[2,3]
Definition - UPFs
Ultra-processed foods (UPFs) are a category of manufactured food products that have undergone extensive processing and contain several to many additives, including questionable preservatives, taste enhancers and flavourings, and other artificial ingredients, and various chemicals ranging in toxicity.
It has been recognised universally that UPFs have minimal whole or natural ingredients. Some have no natural ingredients at all (e.g., gravy powders). UPFs include things like ready-made meals, tin foods (e.g., baked beans, tinned soups), sausages (including hot dogs) and most minced products (e.g., nuggets), meat alternatives (vegan) products, sugary drinks and candy, packaged snacks (e.g., biscuits, cakes, pancakes, crips and anything that comes in a bag claiming to be healthy: quinoa or rice cakes, chickpea crisps, tortilla chips, gluten-free crackers, keto muffins), breakfast cereals, ice-creams and processed spreads. The list goes on and on…
If you rarely cook from scratch, then you may consume an excessive amount of UPFs and little natural, wholesome foods, including freshly steamed vegetables, if any at all. UPFs are usually cheaper (which begs the question: what ingredients have been used to be so cheap?!?) and are strategically found in all supermarkets and food stores.
The disproportionate display of UPFs in those stores is so flagrant that those places have now come up with “Healthy Aisles.” So, if one aisle proposes “healthier” options, what are the other aisles selling?
YES, you got it…
ULTRA-ADDICTIVE UNHEALTHY JUNK!!!
“If you rarely cook from scratch, then you may consume an excessive amount of UPFs.”
UPFs and Metabolic Dysfunction
Numerous observational studies have shown that regular consumption of UPFs is associated with obesity, as well as other conditions including cardiovascular diseases (French study: 105,159 participants over an average 5-year period)[4] and cancer. However, until recently, there was little evidence to support the causal relationship between UPFs and weight gain.
A 2019 randomised controlled trial published in the journal Nature provides much-needed insight into this link. In this study, 20 participants stayed at a research facility for four weeks. They were given either an ultra-processed (UP) or a minimally processed (MP) diet for two weeks, followed by the alternate diet for another two weeks. Meals and snacks provided in the UP and MP diets were matched for equivalent calories, sugar, fat, sodium, fibre, and macronutrients. Participants were allowed to eat as little or as much as they wanted ("ad libitum").
Over the course of the study, researchers measured body weight changes and the amount of energy consumed. They found that the daily average energy intake was over 500 kcal higher when consuming the UP diet. This translated to ~1 kg of weight gain on the UP diet, and ~1 kg of weight loss on the MP diet (for a total difference of 2 kg).
Carbohydrate, fat, and sodium intake were also higher on the UP diet. Protein, sugar, and fibre intake were the same between diets.
There were no differences in ratings of hunger, fullness, and satisfaction between diets despite consuming 500 kcal more per day on the UP diet. This suggests that UPFs may promote overeating independent of hunger signals.
The authors of the study concluded that UPFs increase energy intake and weight gain, and are likely a major driver of our obesity epidemic.
These findings have important implications for public health. Given the growing prevalence of UPFs in the modern diet, it is clear that we need to take steps to reduce our consumption of these foods.
“UPFs may promote overeating independent of hunger signals.”
UPFs and Increased Calorie Intake
If a product is made of ultra-refined ingredients and extracts, a lot of sugar, salt and various taste enhancers like MSG (to make those food palatable and ultra-addictive), hydrogenated and trans fat, and contains little wholesome ingredients, fibre and bioavailable vitamins and minerals, how can these manufactured products not contribute to weight gain when consumed regularly or even obesity when many ingredients used in UPFs have been identified as pro-inflammatory and gut irritants?
Research has also shown that some ingredients have a direct impact on gut microbiota diversity and function, leading to increased intestinal permeability and pro-inflammatory byproducts such as endotoxins, histamine and alcohol (the leading cause of NAFLD — non-alcoholic liver disease). Those same compounds have also been found to inflame the brain and be responsible for lower cognition and depression.
Let’s look at some food labels:
Well-known gravy powder ingredients:
Potato Starch, Maltodextrin, Palm Oil, Salt, Wheat Flour (With added Calcium, Iron, Niacin, Thiamin), Colour (E150c) Sugar, Flavourings (contain Barley), Flavour enhancers (E621, E635), Emulsifier (E322)
Chicken gravy from the same manufacturer:
Maltodextrin, Potato Starch, Salt, Vegetable Oils (Palm, Rapeseed), Flavour Enhancers (Monosodium Glutamate, Disodium 5'-Ribonucleotides), Colour (Ammonia Caramel), Chicken Powder (2%), Flavourings, Autolysed Yeast, Onion Powder, Emulsifier (SOYA Lecithin), Chicken Fat, Onion Extract, Spice, Black Pepper Extract, Sage Extract, Onion Oil, Rosemary Extract.
N.B. Remember that ingredients are listed in order of content. The ingredient with the highest content is at the top of the list and the ingredients with the least content are featured at the end of the list. Chicken powder (there is some chicken after all!!! Some waste from the meat industry???) is at 2%. This means that the ingredients following chicken powder are of the same content or lower (2% to 0.01%) and that the bulk of the products is made up of the ingredients listed before it.
Well-known Breakfast Cereals:
Corn flour blend (whole grain yellow corn flour, degerminated yellow corn flour), SUGAR, wheat flour, whole grain oat flour, modified food starch, contains 2% or less of vegetable oil (hydrogenated coconut, soybean and/or cottonseed), oat fibre, maltodextrin, salt, soluble corn fibre, natural flavour, red 40, yellow 5, blue 1, yellow 6, BHT for freshness. Vitamins and Minerals: Vitamin C (ascorbic acid), reduced iron, niacinamide, vitamin B6 (pyridoxine hydrochloride), vitamin B2 (riboflavin), vitamin B1 (thiamin hydrochloride), folic acid, vitamin D3, vitamin B12.
N.B. There is little evidence to suggest that “enriched” manufactured food products offer any health benefits because the laboratory-made vitamins and minerals added to the recipe (to replace the naturally-occurring vitamins and minerals lost during the extensive processing stages) are often not recognised by the body and, therefore, poorly assimilated.
Another well-known Breakfast Cereal:
Whole Grain Wheat, Sugar, Glucose Syrup, Honey, Contains 2% Or Less Of Palm Oil, Fruit Juice For Color, Salt, Canola Lecithin, Mixed Tocopherols (Vitamin E) for freshness. New recipe (previous ingredients: SUGAR, Wheat, Dextrose, Honey, contains 2% or less of vegetable oil (hydrogenated or partially-hydrogenated soybean), Salt, Caramel Colour, Soy Lecithin, BHT for freshness).
Hot dog ingredients (sold in Aldi):
Mechanically separated chicken, pork, corn syrup, water, 2% or less of: modified food starch, natural flavourings, salt, potassium lactate, beef, sodium phosphates, paprika, sodium diacetate, sodium erythorbate, sodium nitrite, extractives of paprika.
Sausage ingredients (sold in Tesco):
Pork (40%), Water, Rusks, Pork Fat, Wheat Starch. Wheat Protein, Salt, Stabilisers (Tetrasodium Disphophate, Disodium Diphosphate), Dextrose, Wheat Flour, Yeast Extract, Spice Extracts, Preservative (Sodium Metabisulphite), Antioxidant (Ascorbic Acid), Dried Herbs (Marjoram), Sage Extract, Rusks (contains Wheat Flour, Salt, Raising Agent (Ammonium Bicarbonate), Spice Extracts (contain Pepper, Nutmeg, Mace, Cardamom).
References
1. Huang PL. (2009). A comprehensive definition for metabolic syndrome. Disease Models & Mechanisms. 2(5-6), pp. 231-237. doi:10.1242/dmm.001180
2. Grundy, SM. et al. (2005). Diagnosis and management of the metabolic syndrome: An American Heart Association/National Heart, Lung and Blood Institute scientific statement. Circulation. 112, pp. 2735–2752.
3. Kahn, R. et al. (2005). The metabolic syndrome: Time for a critical appraisal. Joint statement from the American Diabetes Association and the European Association for the Study of Diabetes. Diabetologia. 48, pp. 1684–1699
4. Srour, B. et al. (2019). Ultra-processed food intake and risk of cardiovascular disease: Prospective cohort study (NutriNet-Santé). BMJ. doi:https://doi.org/10.1136/bmj.l1451
5. Fiolet, T. et al. (2018). Consumption of ultra-processed foods and cancer risk: results from NutriNet-Santé prospective cohort. BMJ. 360. doi:https://doi.org/10.1136/bmj.k322