For today’s edition of Dear Mark, I’m answering five questions taken from this Twitter thread . First, does collagen offer anything special above and beyond glycine? Second, what’s the relationship between keto and gallstones? Third, do I recommend eating raw liver, and why or why not? Fourth, why does one reader’s scalp itch when eating stevia? And finally, what’s the best way to lose fat and gain muscle at the same time?
If collagen is broken down into amino acids in the gut before being absorbed, is it just the amino acid profile (i.e. high glycine) that makes it so beneficial? Anything else?
Glycine is a major reason why we need collagen in our diets, but it’s not the only one.
When you feed people collagen derived from pork skin, chicken feet, and cartilage, many different collagenous peptides appear in the blood . You don’t get any of these from isolated glycine:
Proline-hydroxyproline, a peptide with protective effects on osteoarthritic cartilage degradation .
Glycine-proline-hydroxyproline, a peptide that makes it into the blood and turns into proline-hydroxyproline, which makes it into the skin .
Collagen peptides have beneficial effects above and beyond glycine alone—although glycine is great for balancing out methionine intake from muscle meat consumption. It’s also been used in several studies to improve multiple markers of sleep quality .
A family member has a complicated health history including cancer and wants to eat keto. But, now she finds she has gallstones. Any thoughts on a good way to attack this complicated issue?
Has your family member already gone keto? Did going keto come before the gallstone reveal?
If so, that’s actually normal.
The primary role of the gallbladder is to collect bile from the liver, concentrate it into potent super-bile (my term), and release the concentrated bile to break up incoming dietary fat into smaller molecules that lipase can attack and digest. Dietary fat is the biggest driver of gallbladder emptying .
If the gallbladder isn’t regularly emptied, gallstones can form. Usually made of hardened cholesterol, gallstones are quite common and often produce no symptoms. Problems arise when normal gallbladder emptying flushes out a stone small enough to make it into but too large to pass through the bile duct and a blockage occurs. Gallstones can also directly damage the walls of the gallbladder, leading to cholecystis, or gallbladder inflammation.
A high-fat diet can exacerbate or even uncover gallstone issues by increasing gallbladder emptying. Remember: the more fat you eat, the more often you empty your gallbladder—and everything in it.
But high-fat diets don’t generally cause gallstones to form. They only reveal pre-existing ones. The biggest risk factors for gallstone formation are:
- A high intake of high-glycemic carbohydrates .
- High estrogen  levels, which concentrate cholesterol deposition in the gallbladder. This is why women, especially pregnant women and/or those taking hormonal birth control, are more likely to have gallstones.
- Obesity, which also increases cholesterol levels in the gallbladder.
- Weight loss, with a caveat: high-fat weight loss diets reduce and even prevent gallstone formation. In fact, when you compare people who lose weight on a low-fat diet to those who lose it on a high-fat diet, research shows  that 45% of the low-fatters develop gallstones while none of the high-fatters develop them.
Once the gallstones are all clear, keep up with the keto eating, as eating more fat will keep your gallbladder regularly flushed and clear of stones.
Is Raw Liver safe to eat?
I’ve eaten raw liver before. I know people who eat raw liver. I can’t recommend it, however, because I don’t know what kind of liver you have access to. Who raised the animal? What did it eat? What were the processing conditions?
But because I know people are going to try this…
Freeze it first for several days.
Buy from a trusted source.
Buy only liver from well-raised, grass-fed, organic animals.
If it looks unhealthy, it probably is. I would never eat a pale, flaccid liver with ugly spots, cooked or raw.
Don’t eat raw (or even medium) pork liver. A huge percentage of pigs carry the Hepatitis E virus, which is transmittable to humans and concentrates in the liver.
Why does stevia make my scalp itch?
Stevia can be an allergen actually. It’s not very common, but as more and more people use stevia, more will be revealed to have an allergic reaction.
I’d just skip it.
Is it possible to gain muscle and lose weight with properly timed IF around workouts?
It is possible, although you may not actually lose weight, but rather body fat (which is better).
The best way I’ve seen people do it is the classic Leangains method.
Fast from 8 p.m. to 12-1 noon.
Fasted workout in the afternoon, perhaps with a little BCAA or whey isolate before the workout. Lift heavy, compound movements.
After the workout, walk for 20 minutes. Brisk pace to utilize all the free fatty acids swimming around.
Then eat. If you’re going to eat carbs, do it in this meal and keep the fat low-to-moderate. Load up on protein.
Eat as much as you like until 8 p.m.—the end of your eating window. Favor protein and, again, if you’re eating carbs keep fat lower than usual.
Maintain the fasting period every day. On rest days, eat low/no carb and higher fat. Protein always high. Go for walks on rest days.
That’s it. That usually works really well, but it presupposes you have a flexible schedule and can actually train in the afternoon whenever you want. Your mileage may vary—though it will work at any time.
Muscle gain won’t be as rapid as it would drinking a gallon of milk a day, eating pizza smoothies, and cramming ice cream made with whey protein at night, but it will minimize fat gain and perhaps even help you lose fat as you gain muscle. No guarantees, but it’s the best method I’ve seen.
That’s it for today, folks. Thanks for reading, take care, and be sure to leave a comment down below if you have any questions.