🍞 Replacing carbs with fats and protein improves liver health. But how?

General consensus for reducing liver fat (fatty liver disease) has been following a diet low in fat (<30% of energy from fat) and rich in low-glycemic index carbs (50%–60% energy).

However, emerging evidence paints a different picture.

Two recent studies in people with type 2 diabetes found that replacing dietary carbs with protein and fat improves fat metabolism in people with T2D, independently of changes in body weight.

This was likely due to reduced fat accumulation in the liver and improved insulin sensitivity; both having a cardioprotective effect.

The first study was a calorie matched study: 30 participants followed either a high-protein diet (carbs 30%, protein 40%, fat 30%) or a conventional diet to manage diabetes (carbs 50%, protein 17%, fat 33%) for 6 weeks. The aim was weight maintenance.

The second study was a calorie restriction study: 72 participants followed the same two diets, but the aim was to achieve a 6% weight loss.

In both studies, the high protein group reduced liver fat by at least 26% more than the standard diet.

🥊 Punchline

Increasing the ratio of protein and fats to carbs for people with type 2 diabetes help reduce fat accumulation in the liver and overall metabolic health.

🍩 How does fructose fuel cancer?

A recent study helps us understand how fructose, after fluxing through the liver, can support the production of building blocks for multiple tumours.

Several experiments using high-fructose corn syrup (HFCS; the most abundant and dense source of fructose) revealed that HFCS supplementation resulted in faster tumour growth compared without changing body weight.

This included skin, breast and cervical cancers in animal models and across species.

The mechanism relies on a key enzyme of fructose metabolism, called ketohexokinase (KHK).

Cancer cells lack sufficient levels of KHK to process fructose and so hijack other energy systems.

The liver metabolises fructose. The cancer cells then uptake the by-products of fructose metabolism and convert them into other molecules, called “phosphatidylcholines”.

This is very useful for the cancer cells since fructose metabolism supplies major building blocks required for tumour growth.

🥊 Punchline

Fructose metabolism in the liver aids tumour cells growth in animal studies. Reducing fructose intake could improve liver health and cancer prevention.

🍣 More oily fish = lower risk of prostate cancer?

A recent study investigated if increasing intakes of omega-3 and lowering intake of omega-6 was beneficial in men with prostate cancer.

Men with low-grade cancer were either on a low fat diet (<30% of calories from fat) or on a standard diet.

The low fat diet was low in omega-6 rich foods (e.g. fried foods, highly processed foods, chips, baked goods) and high in omega-3 rich foods (e.g. salmon and tuna), on top of fish oil supplementation.

The high omega-3 low omega-6 diet improved tumour biomarkers by 15%.

While the same biomarkers worsened by 25% in the control group. Weight did not change in either groups.

It may seem that a higher ratio of omega-3 / omega-6 promotes better health, but funding from the Seafood Industry Research Fund raises questions.

The results don’t lie, but it’s likely that omega-6 rich foods are higher in inflammatory compounds created during processing that may increase oxidative stress (aka heavily processed foods). And so reducing the intake of these foods could be what drives the outcomes.

🥊 Punchline

A high omega-3 / omega-6 ratio could improve outcomes in men with low grade prostate cancer. However, reducing highly processed foods rich in omega-6 (e.g. convenience foods processed with seed oils) and increasing nutrient dense foods could make the outcomes even better.