Active Low-Carber Forums
Atkins diet and low carb discussion provided free for information only, not as medical advice.
Home Plans Tips Recipes Tools Stories Studies Products
Active Low-Carber Forums
A sugar-free zone


Welcome to the Active Low-Carber Forums.
Support for Atkins diet, Protein Power, Neanderthin (Paleo Diet), CAD/CALP, Dr. Bernstein Diabetes Solution and any other healthy low-carb diet or plan, all are welcome in our lowcarb community. Forget starvation and fad diets -- join the healthy eating crowd! You may register by clicking here, it's free!

Go Back   Active Low-Carber Forums > Main Low-Carb Diets Forums & Support > Low-Carb Studies & Research / Media Watch > Low-Carb War Zone
User Name
Password
FAQ Members Calendar Mark Forums Read Search Gallery My P.L.A.N. Survey


Reply
 
Thread Tools Display Modes
  #1   ^
Old Wed, May-01-19, 09:12
teaser's Avatar
teaser teaser is offline
Senior Member
Posts: 15,075
 
Plan: mostly milkfat
Stats: 190/152.4/154 Male 67inches
BF:
Progress: 104%
Location: Ontario
Default tryptophan versus leucine, serotonin

First: whey protein will probably not decrease your lifespan. I don't buy this at all. But it's an interesting study, that has nothing to do with whey protein. So of course the headline is all about whey protein...


https://www.sciencedaily.com/releas...90430091826.htm

Quote:
Put down the protein shake: Variety of protein better for health
Popular protein great for increasing muscle mass, but could reduce your life-span -- researchers say to vary protein intake

Amino acids have long been touted by the fitness and bodybuilding communities for their muscle building benefits. From ultra-bulk protein powders to lean mass-promoting snack bars, there's no shortage of products available for those seeking a muscle boost.

However, protein's popularity has also meant that less attention has been paid to researching its potentially negative side-effects.

Published today in Nature Metabolism, new research led by academics from the University of Sydney's Charles Perkins Centre, Professor Stephen Simpson and Dr Samantha Solon-Biet, suggests that while delivering muscle-building benefits, excessive consumption of branched-chain amino acids (BCAAs) may reduce lifespan, negatively impact mood and lead to weight gain.

BCAAs great for adding muscle mass, but science says you could pay for it later

Dr Solon-Biet's research has investigated the complex role nutrition plays in mediating various aspects of metabolic health, reproduction, appetite and ageing.

"While diets high in protein and low in carbohydrates were shown to be beneficial for reproductive function, they had detrimental effects for health in mid-late life, and also led to a shortened lifespan," she explained.

"What this new research has shown is that amino acid balance is important -- it's best to vary sources of protein to ensure you're getting the best amino acid balance."

BCAAs could influence mood -- and lead to overeating

The current research examined the impacts that dietary BCAAs and other essential amino acids such as tryptophan had on the health and body composition of mice.

"Supplementation of BCAAs resulted in high levels of BCAAs in the blood which competed with tryptophan for transport into the brain," explained Academic Director of the Charles Perkins Centre's and researcher from the School of Life and Environmental Sciences Professor Stephen Simpson.

"Tryptophan is the sole precursor for the hormone serotonin, which is often called the 'happiness chemical' for its mood-enhancing effects and its role in promoting sleep. But serotonin does more than this, and therein lay the problem," he said.

"This then lowered serotonin levels in the brain, which in turn was a potent signal to increase appetite. The serotonin decrease caused by excess BCAA intake led to massive overeating in our mice, which became hugely obese and lived shorter lives."

Mice were fed double the normal amount of BCAAs (200%), the standard amount (100%), half (50%) or one fifth (20%) for life. Mice who were fed 200% BCAAs increased their food intake, resulting in obesity and a shortened lifespan.

Increase protein variety for health benefits

Qualified dietitian and public health nutritionist from the University of Sydney's School of Life and Environmental Sciences Dr Rosilene Ribeiro recommends eating a wide-range of proteins.

It's important to vary protein sources in order to get a variety of essential amino acids, through a healthy and balanced diet rich in fibre, vitamins and minerals.

BCAAs are essential amino acids present in protein-containing foods, with red meat and dairy being the richest sources. Chicken, fish and eggs are also nutritious sources of BCAAs.

Vegetarians can find BCAAs in beans, lentils, nuts and soy proteins.

Foods rich in tryptophan include seeds and nuts, soy beans, cheese, chicken,turkey and interestingly, crocodile.

About BCAAs

BCAAs are a group of three essential amino acids: leucine, isoleucine and valine, and are most commonly found in red meat and dairy. Whey protein -- the most popular form of fitness protein -- is made from dairy by-products and contains high levels of BCAA.


Wasn't quite sure where to put this.

Potatoes not Prozac and other carbs versus depression plans are based on some tryptophan versus leucine studies. It's a total misreading of the science. Feed an animal some carbohydrate, almost protein-free--insulin etc. increases protein synthesis, this draws leucine and other branched chain amino acids out of circulation, increased tryptophan to leucine etc. ratio results in increased tryptophan across the brain barrier, and increased serotonin. But it only works with very low protein, potatoes have too much protein for the effect.

This study also looks a bit misreported. They talk about "foods rich in tryptophan" or leucine. But

Quote:
Mice were fed double the normal amount of BCAAs (200%), the standard amount (100%), half (50%) or one fifth (20%) for life.


This is too precise. Without a semi-purified diet, with added branched chain amino acids, they couldn't get these numbers while keeping things like protein content of the diet constant.

Quote:
Here, we show that when dietary BCAAs are varied against a fixed, isocaloric macronutrient background, long-term exposure to high BCAA diets leads to hyperphagia, obesity and reduced lifespan.


and

Quote:
These effects are not due to elevated BCAA per se or hepatic mammalian target of rapamycin activation, but instead are due to a shift in the relative quantity of dietary BCAAs and other amino acids, notably tryptophan and threonine. Increasing the ratio of BCAAs to these amino acids results in hyperphagia and is associated with central serotonin depletion.


they don't quite specifically say that protein intake was kept constant, but that would be too much of a confounder, if they didn't keep it constant, I'm not sure how they could assume a ratio of this to that rather than absolute quantity of the aminos was to blame.

Going from this, to food...Eating twice as much turkey is not going to increase leucine: tryptophan in the diet as a ratio. Can we make assumptions that high leucine whey will give poor results? Wait a minute, this is a mouse study. Switching mice to whey versus casein, at least, generally improves things.

Cronometer gives whey as a fairly good source for leucine. But at a dose that shows 100 percent of the day's "requirement" for leucine, it shows 200 percent of the requirement for tryptophan. Looking at various other protein sources, that's a pretty good ratio if you think increasing tryptophan:leucine is a good idea.

I'm not crazy about whey protein because it's got all the non-protein nutrition removed. But as a protein, it's probably fine.
Reply With Quote
Sponsored Links
  #2   ^
Old Wed, May-01-19, 11:21
Ms Arielle's Avatar
Ms Arielle Ms Arielle is offline
Senior Member
Posts: 19,176
 
Plan: atkins, carnivore 2023
Stats: 200/211/163 Female 5'8"
BF:
Progress: -30%
Location: Massachusetts
Default

My understanding is this.

Tryptophan is a very small percentage of the amino acid/protein content. Ricotta is 0 .12g tryptophan per 100g serving. Three times the next highest source plain nongreek yogurt. Other sources are puny.

The gut makes 90-95% of the total seratonin. This cannot pass the blood brain barrier. The brain apparently must makes its own supply. This requires tryptophan to cross. The problem seems to be it is competeing with other proteins. Two mechanisms I found are eating carbohydrates at the same time or working out to fatigue.

I donot fully understand the biochemistry behind either.

My son and I relied on 5-HTP but it has side effects reguarding growth of a youngster.

We are trialing lc ricotta pancakes with real maple syrup.

As for only consuming BCAA 's, IMHO eating a full spectrum of amino acids via real meat like beef, lamb, fish, etc is far more beneficial.

My son was using whey protein to bulk up. When he stopped bothering with protein shakes, I said nothing. Our goal is a healthy mucsle mass from some weight lifting, running, hard farm work and eating high quality proteins like animal meat.

As for appetite, and obesity I suspect real life is more complicated than a mouse study. Currently my youngest, 15yo, is very lean with a five pack,lol, and noticeably larger bicepts. Without using whey protein. He has youth and sports on his side for now.

His older brother needs the seratonin boost, and if that includes adding body fat, yeah. Cant pinch 1/2 inch on that kid. He needs more mucsle and more body fat.

Maybe worth trying him on a n=1 experiment with more whey. Bought reg yogurt instead of greek for his lunch , ricotta pancakes with maple syrup for breakfast. Will see how this works out.
Reply With Quote
  #3   ^
Old Wed, May-01-19, 11:22
Ms Arielle's Avatar
Ms Arielle Ms Arielle is offline
Senior Member
Posts: 19,176
 
Plan: atkins, carnivore 2023
Stats: 200/211/163 Female 5'8"
BF:
Progress: -30%
Location: Massachusetts
Default

Ps. If whey increases body weight, does that mean milk does too ??
Reply With Quote
  #4   ^
Old Wed, May-01-19, 12:04
CityGirl8 CityGirl8 is offline
Senior Member
Posts: 856
 
Plan: Protein Power, IF
Stats: 238/204/145 Female 5'8"
BF:53.75%/46.6%/25%
Progress: 37%
Location: PNW
Default

Quote:
"While diets high in protein and low in carbohydrates were shown to be beneficial for reproductive function, they had detrimental effects for health in mid-late life, and also led to a shortened lifespan," she explained.
This seems not to have anything to do with the study that's being reported on and seems to really confuse the issue. As Teaser noted, they must have been trying to hold total protein constant while varying the BCAAs, if that's what they were trying to get results on. So none of the diets should have been high protein--or all of them. I think that quote is just a random dig at low-carb diets.
Reply With Quote
  #5   ^
Old Wed, May-01-19, 13:20
bluesinger's Avatar
bluesinger bluesinger is offline
Doing My Best
Posts: 4,924
 
Plan: LC/CancerRecovery
Stats: 170/135/130 Female 62 inches
BF:24%
Progress: 88%
Location: Nevada Desert, USA
Default

Oh my. I should have been dead years ago.
Reply With Quote
  #6   ^
Old Tue, Jun-04-19, 21:54
rightnow's Avatar
rightnow rightnow is offline
Every moment is NOW.
Posts: 23,064
 
Plan: LC (ketogenic)
Stats: 520/381/280 Female 66 inches
BF: Why yes it is.
Progress: 58%
Location: Ozarks USA
Default

So... if I'm reading this right...

...intentionally, substantially skewing your nutrition to somewhat deprive yourself of certain required nutrients...

...is less good.

Getting a decent variety of required nutrients so you are not uber-high in one area and super-low in another...

...is more good.

I'm surprised it required a rodent study to figure that out.

When these scientists are old they will rediscover how eating 'whole animal' (wider range of amino acids) is even healthier than eating nothing but one type of muscle meat exclusively. Go figure.

PJ
Reply With Quote
  #7   ^
Old Wed, Jun-05-19, 05:03
GRB5111's Avatar
GRB5111 GRB5111 is offline
Senior Member
Posts: 4,036
 
Plan: Very LC, Higher Protein
Stats: 227/186/185 Male 6' 0"
BF:
Progress: 98%
Location: Herndon, VA
Default

Quote:
Originally Posted by rightnow

When these scientists are old they will rediscover how eating 'whole animal' (wider range of amino acids) is even healthier than eating nothing but one type of muscle meat exclusively. Go figure.

PJ

Well stated.
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -6. The time now is 06:04.


Copyright © 2000-2024 Active Low-Carber Forums @ forum.lowcarber.org
Powered by: vBulletin, Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.