Hi everyone. I'm new to PaleoHacks as I user but I've been reading a lot of your posts over the past several months. Thank you for all of your research and anecdotes which coupled with some Google Scholar hunting guided me in eventually adopting an LCKD which has helped me loose wait, attain higher concentration levels at work and NOT fall asleep at my desk between meals. I don't keep a diet journal :(, but I think me diet might high in fat: lots of butter, heavy creams, cheeses, fatty meats, coconut oils, etc.
Sorry for the rather controversial question, but this is reference to a cognitive-dissonance-challenging study I found this morning A high-fat diet impairs cardiac high-energy phosphate metabolism and cognitive function in healthy human subjects (http://www.ajcn.org/content/93/4/748.abstract). I was almost worried until I saw it was 5d study. Nonetheless, has anyone read the full text to the study or have any other insights to share? I feel my own anecdote following several months of adhering to the diet resolves to me personally any fear of cognitive impairment, but cardiac function is something I don't know how to assess as well; so there's still a small pin of worry in me from this.
I want to answer this question, but my brain is like, all cloudy. Must be the eggs, coconut oil, almonds and chocolate I had for lunch.
Seriously, 75% of calories as fat (what kind we don't know) is a very low carb/ketogenic type of diet. Ever heard of the "low carb flu"? The first week or two, people tend to be lightheaded, headachey, wonky or worse. They performed worse on cognitive function tests? No duh!
I sometimes eat that way, but I add some carbs when my hands/feet start getting cold. (I normally have overly hot feet/hands and rarely wear a coat unless it drops below 30.)
Nobody said paleo has to be 75% fat! Ketogenic diets can be useful for certain medical conditions, but paleo doesn't have to be ketogenic. Just eat realz fud! Eat some meat, eggs, some fruit and vegeetabulz and other real things. It's incomprehensible that eating in line with our evolutionary past would be unhealthy.
Also, the 9% reduction in PCr/ATP could probably be explained by the fact that the heart loves to burn ketones! Other sources of energy would HAVE to be downregulated. This is not an indication of impending heart failure (as it might be for someone not generating tons of ketones). Either the researchers are stupid or (more likely) intentionally trying to discredit ketogenic diets. Very unethical IMHO.
Oh! This study was paid for by the British Heart Foundation. They like to give out healthy eating advice like this:
"Eating breakfast helps children stay alert during lessons and energised throughout the day. Try wholegrain cereals topped with low fat yoghurt and fruit to help them reach their five-a-day.
"Pack lunchboxes with healthy eating options, like pittas and bagels filled with tuna and sweetcorn. Low-fat yoghurt and a small packet of dried fruits will satisfy a sweet tooth.
"For after-school snacks make sure there are fruit and nuts to hand. Beans on toast or mashed banana sandwiches are healthy ideas for really hungry youngsters."
The usual memes of low fat, healthy whole grains, 5 a day, avoid red meat, blah, blah, blah. A bunch of corporatist shills, if you ask me. (Did you ask me?)
Search Paleo Hacks and the all mighty Google. Seth Roberts. Math. Butter.
I suspect it depends on the type of fat, but butter has been shown to increase cognitive function, and I find being in a state of ketosis helps my brain work better. Of course, I pair my ketosis with coffee, which may or may not have an impact.
If it makes any difference, I'm a computer programmer by trade, and a pretty darn good one, so my brain HAS to work. My livelihood depends on it. Low carb/high fat diets work great for me.
Also, regarding cardiac function, I've read that the heart is 17% more efficient when running on ketones.
EAT YOUR FAT == LIVE LONG AND PROSPER
A high fat diet (of course no soy bean oil etc., there's no way this could be healthy) leads automatically to lower carb consumption. And with a low carb intake, ketosis becomes likely.
But now there are several studies out there that show the neuroprotective properties of ketone bodies.
Very unlikely this could be brain damaging. Plus, I don't think evolution wants us to get stupid from depleting our body fat storages...
EDIT: maybe they have testet them during keto adaption, in my experience the first 3 weeks are brain-standby-mode
Based on my research and reading ray peat If the FFA's are saturated most of the harmful effects can be mitigated. The problem is when people are coming from a SAD and have a high concentration of PUFA in there tissue, when the PUFA is released as FFA's they have many negative metabolic consequences. This is most likely what is happening in the study but I can't be 100% sure.
Personally I wouldn't do a ketogenic diet long term, too many untested variables and some info that it might not be the best in regards to immune function.
Your brain runs on glucose primarily as well so it only makes sense its gonna run the best on its preferred fuel.
I don't have the full text, but I can imagine what would be contained. It's simply incredibly difficult to draw meaningful conclusions from trying to control human diets for a short period of time.
I wish I could comment on more of the details, but I can tell you, just from the abstract, that they've been sloppy with their terminology: their definition of "high fat/low carb" probably isn't mine, and may not be yours.
They say that the "high fat" diet they used got 75%(!) of the calories from fat. That leaves you with 25% to split betw/the proteins and carbs, so I'm betting that the carbs came out at 10% or less.
And if that's the case, that's not just low carb: that's a very low carb diet; there's a big difference. (And I really can't see them giving more carbs than protein, can you?)
So it looks like they haven't really established that their results hold true for what most folks call "low carb/high fat," just that there's a concern on Very High Fat/Very Low Carb diets.
I'm not a dr., and this is not medical advice, but if your fat intake--and, more importantly, your carb intake--isn't as out of balance as their "high fat" diet, I'm thinking you're probably okay.
From my own experience of food and cognitive test tracking, I perform significantly better when I eat a higher fat diet, which does not mean ZC or even VLC. I've only been tracking for the last month and the fat I've "supplemented" with is lard. My results have been similar to Seth Roberts'.
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