See below description for a summary of stuff talked about in the lecture.
Obesity is a condition of excess fat accumulation in adipocytes where the person is literally stuck in storage mode diverting a disproportionate amount of calories into fat cells as opposed to oxidation. Thus it is more productive to think of obesity as a problem in ‘energy flow’ rather than energy expenditure (i.e., calories in, calories out).
The most efficient approach to accelerate the body’s ability to access and burn body fat is to restrict dietary carbohydrate while increasing fat intake for a period of several weeks, after which fatty acids and ketones become the primary fuel at rest and during submaximal exercise.
The coordinated set of metabolic adaptations that ensure proper inter-organ fuel supply in the face of low carbohydrate availability is referred to as keto- adaptation. This unique metabolic state has recently been shown to have widespread and profound therapeutic and performance-enhancing effects ranging from reversing type 2 diabetes to shrinking tumors to allowing ultra-endurance runners to set course records.
This presentation will discuss the physiologic effects of very low carbohydrate diets with an emphasis on their unique effects on both features of metabolic syndrome and human performance.
I wrote these down as the video played, hopefully caught the essence in shorthand fairly well without making stuff up.
- LC diets remain a fringe concept
- scientists don’t like to admit being wrong
- cognitive dissonance
- politics trumps science
- but they are coming around, and will likely advocate LC eventually
- Sweden first country to embrace HFLC diet as national guideline – Oct 2013
- The obesity epidemic
- increasing despite ridiculous amount of effort
- Exercise and weight loss
- identical twins, exercise twice/day for 2 hours – 624kcal
- huge variability overall, but concordance within twin-pairs, response is almost completely down to genetics
- exercise for health, not to lose weight
- One size fits all approach (pyramid/myplate)
- but doesn’t particularly fit much of the population at all
- need to personalise nutrition
- Carbohydrates – not just fuels; potent metabolism regulator
- wide range of carbohydrate tolerance
- evolved with a hugely limited carbohydrate intake
- very wide variability between people with more carbs, but variability in response on very low level of carbs, very conserved trait
- History of last 40 years
- massive increase of carbohydrates
- funnily enough – obesity and degenerative diseases too
- Blood glucose levels
- 2 teaspoons/8g in average
- average carby meal has 10x that
- Fate of carbohydrates
- healthy person takes up to muscles and glycogen
- too much increases lipogenesis (creation of fat)
- VLDL’s and saturated fat – palmitic acid
- cascade of collateral damage -> metabolic syndrome
- Insulin resistance = carbohydrate intolerance
- higher tolerance means more diet options
- ¾ of Americans are somewhat carb intolerant
- Atkins vs Ornish diets
- LC always lost plenty of weight regardless of intolerance
- LF sometimes lost weight, much more variable
- Carbohydrate intake is biggest factor in determining glucose vs fat based metabolism
- fat metabolism associated with cancer regression, life extension, etc
- Insulin most important inhibitor of lipolysis
- small reductions in insulin = dramatic impact on fat burning
- Carbs => sugar spike => insulin spike = sugar crash
- insulin spike blocks fat release
- Ketones very important evolutionarily
- big player in surviving throughout history
- most important role is feeding the brain
- ketone terminology
- ketosis loosely known as blood levels > 0.5 mmol/L
- Adaptation takes several weeks to months
- optimal ketone levels are 0.5-3.0 mmol/L
- adaptation alters hypoglycemic threshhold – as low as 25mg/dl BG is tolerable, normally would be in a coma
- Provocative effects of ketones
- “clean burning fuel” – don’t generate as many free radicals
- higher antioxident defense
- greater efficiency providing energy
- act as signals to increase gene expression against oxidative stress
- Recent science
- most coming to same conclusion: LC is good for most biomarkers/health
- despite the dearth of well-controlled studies
- Dietary saturated fat and heart disease
- 3 recent meta-analyses all concluded no correlation
- replacing sat fat with carbs increases risk of coronary event
- plasma sat fat predicts heart disease
- LC diet had 3x amount of sat fat than LF
- plasma sat fat much higher in LF diet
- Combining sat fat and carbs – eg steak and potato
- setting up for metabolic syndrome
- swap out spud for veggies – now burning it instead of storing
- “You are what you save from what you eat”
- Beneficial effects of ketogenic diet in obese diabetic folk
- lower glucose/trigs/LDL-C/total cholesterol
- increased HDL-C
- most cancers have insulin receptors
- less glucose is a good thing
- Neuroprotetive role of ketones
- mitochondrial disorders
- brain trauma
- wound healing
- Athletic performance
- Tim Olsen winning 100 mile events
- doing lab testing of athletes
- peak fat oxidation of LC athletes is double normal elite athletes
- military researching the effects
- Dialling in the right level of carbs for ketosis
- wide variability between individuals
- should test to find your level
- Example of meals from a day of a study
- subjects have no inclination to snack
- wake up not hungry
- feel great, euphoric
- Key to health and performance is understanding your own optimum macros
- Example of foods to keep under 30/50g of carbs?
- Real foods, non-starchy/sugary stuff.
- Possible to overdo the diet and waste away?
- You tend to end up at a your genetic set state.
- Low calories allegedly extend life, is that as effective as being ketogenic?
- It seems that the same effects occur in the absence of carbohydrates/insulin, however there’s no hard data yet.
- Do ketones cause problems with uric acid?
- They increase them initially and share the same excretion pathways, but upon adaptation it levels off.
Dr. Jeff Volek is a Full Professor in the Department of Kinesiology at the University of Connecticut where he teaches and leads a research team that explores the physiologic impact of various dietary and exercise regimens and nutritional supplements.
Dr. Volek’s most significant line of work has been a series of studies aimed at better understanding what constitutes a well formulated low carbohydrate diet and the physiological impact on obesity, body composition, fatty acid composition and lipoprotein metabolism, gut micro-biome, adaptations to training and overall metabolic health. This line of work has shown profound effects of ketogenic diets on overall health and well-being, as well as peak performance.
He has published more than 250 peer-reviewed manuscripts, many of which were longitudinal interventions of carbohydrate restricted diets. Specific to low carbohydrate diets, Dr. Volek has authored/co-authored 4 books, 60 peer-reviewed manuscripts and reviews, and delivered over 100 invited presentations on low carbohydrate diets in half a dozen countries at scientific and industry meetings.
Through more than a decade of research dedicated to better understanding low carbohydrate diets, Dr. Volek has accumulated an enormous amount of laboratory and clinical data on how carbohydrate restricted diets affects human physiology, and acquired a unique knowledge pertaining to the individualization and formulation of safe, effective and sustainable low carbohydrate diets.