UPFs gave me wagu thighs

Interesting article reproduced this week in the Financial Times from the annual meeting of the Radiological Society of North America held in Chicago. 

One group reported to the conference that in a study of 60 yr olds, whose diet consisted of approximately 40% so called UPF, but who did not consume excessive calories had ‘fatty thighs’!

They  differentiated between fat outside muscle tissue and fat within muscle tissue. In other words fat pads under the skin making the thigh look ‘fat’ and fat within the tissue itself. To those who eat meat, intramuscular fat is recognised and valued as ‘marbling’ because it enhances both taste, succulence and texture.

No hypotheses were put forward but one more nail in the UPF coffin was hammered home and it drew the usual scoff from the food industry who know that as a collective term UPFs are impossible to define…so are UPFs the bad guys here?

As a biochemist I wondered how quickly an hypothesis could be generated and how well it could be pinned to a modern UPFish diet or not..The answer was .. about 10 minutes.

The beef industry values marbling in meat the ultimate expression being in asian cattle and Wagu steaks. The adipocytes ( fat cells) within muscle are different to those outside tissue and respond to different signals most of which are poorly understood or studied. However mild injury and inflammation increases intramuscular adipocyte activity and fat infiltration in to the tissue. Some cattle are genetically disposed to intramuscular fat infiltration but other than the above the only strategy to increase marbling is to add conjugated linoleic acid to the feed. These are called CLAs and can be synthesised as well as being present in natural foods.

Natural sources of CLAs are basically: milk, cheese and meat.. The highest values I found published when a quick web search was carried out are in milk, ground beef and mozzarella cheese.

So, let me think: latte coffees, burgers and pizzas should max out our CLA intake

There you go, nothing to do with bad stuff in the foods, after all you can get the highest quality of unadulterated ingredients in all three of the foods above, but if you have a latte each day, burgers twice a week and a take away pizza, you’ll probably get wagyu-thighs!

Ps if you are wondering what the intramuscular fat is doing in your muscles, quite simply it is an energy store placed as close as possible to the muscle mitochondria which use fatty acids as slow burn fuel. Ideal for a labourer maybe not ideal for an office worker.