Ketosis – advantaged or misunderstood state? However, so many great questions and comments emerged from the discussion that I realize it’s worth spending much more time on this important and misunderstood topic. In terms of setting expectations, I suspect this series will require at least four parts, after which I hope to get back to finishing up The Straight Dope on Cholesterol series. So, back to the topic at hand. I do suspect part of the issue is that folks don’t understand the actual question. I’ve used the term “metabolic advantage” because that’s so often what folks write, but I’m not sure it has a uniform meaning, which may be part of the debate. I think what folks mean when they argue about this topic is fat partitioning, but that’s my guess. To clarify the macro question, I’ve broken the question down into more well- defined chunks. Does ketosis increase energy expenditure? I am pretty sure when the average person argues for or against ketosis having a “metabolic advantage” what they are really arguing is whether or not, calorie- for- calorie, a person in ketosis has a higher resting energy expenditure. In other words, does a person in ketosis expend more energy than a person not in ketosis because of the caloric composition of what they consume/ingest? Let me save you a lot of time and concern by offering you the answer: The question has not been addressed sufficiently in a properly controlled trial and, at best, we can look to lesser controlled trials and clinical observations to a make a best guess. Believe me, I’ve read every one of the studies on both sides of the argument, especially on the . This particular study sought to compare a non- ketogenic low carb (NLC) diet to a ketogenic low carb (KLC) diet (yes, saying . Table 3 in this paper tells you all you need to know. Despite the study participants having food provided, the KLC group was not actually in ketosis as evidenced by their B- OHB levels. At 2- weeks (of a 6- week study) they were flirting with ketosis (B- OHB levels were 0. M), but by the end of the study they were at 0. M. While the difference between the two groups along this metric was statistically significant, it was clinically insignificant. That said, both groups did experience an increase in REE: about 8. NLC group and about. KCL group (this is calculated using the data in Table 3 and Table 2). These changes represented a significant increase from baseline but not from each other. In other words, this study only showed the reducing carbohydrate intake increased TEE but did not settle the . Subjects being evaluated in such studies will typically be housed in a metabolic ward (don’t confuse a metabolic ward with a metabolic chamber; the ward is simply a fancy hospital unit; the chamber is where the measurements are made) under strict supervision and every few days will spend an entire 2. Not surprisingly, virtually no studies use metabolic chambers and instead rely on short- term measurement of REE as a proxy. A broader question, which overlays this one, is whether any change in macronutrients impacts TEE. Increased FGF2. 1 promotes lipolysis in adipose tissue and the release of fatty acids into the circulation.
Fatty acids are then taken up by the liver and converted into ketone bodies. FGF2. 1 expression in liver and adipose tissue is increased not only by fasting but also by a high fat diet as well as in genetic obesity which, according to these studies, may indicate that increased FGF2. Hence, ketosis may increase TEE either by increasing REE (thermogenic) or AEE (the ketogenic mice move more). Is the ketogenic diet, by maximally reducing insulin levels, maximally increasing lipolysis (which dissipates energy via thermogenic and/or activity ? Bottom line: There is sufficient clinical evidence to suggest that carbohydrate restriction may increase TEE in subjects, though there is great variability across studies (likely due the morass of poorly designed and executed studies which dilute the pool of studies coupled with the technical difficulties in measuring such changes) and within subjects (look at the energy expenditure charts in this post). In other words, is there something “special” about ketosis that increases TEE beyond the dose effect of carbohydrate removal? Many frameworks exist to define physical performance which center around speed, strength, agility, and endurance. Likely. Does ketosis enhance anaerobic power? No. Does ketosis enhance muscular strength? Unlikely. Does ketosis enhance muscular endurance? Like the previous question about energy expenditure, addressing this question requires defining it correctly. In fact, to do so cleanly requires a model where the relationship between these variables is clearly defined. The heart is studied because the work action is (relatively) simple to measure: cardiac output, which is the product of stroke volume (how much blood the heart pumps out per beat) and heart rate (how many times the heart beats per minute). Before we jump into the data, you’ll need to recall two important pieces of physiology to “get” this concept: the acute (vs. Hydraulic work is a bit more nuanced; it measures the mechanical work being done by the fluid.)Adding insulin to a fixed glucose (GI) load increases both cardiac output and hydraulic work, but it’s only significant in the case of hydraulic work. Oxygen consumption was significantly reduced in all arms relative to glucose alone, so we expect the cardiac efficiency to be much higher in all states. Delta G, or Gibbs free energy, is the “free” (though a better term is probably “available” or “potential”) energy of a system. Delta G = Delta H – Temperature * Delta S, where H is enthalpy and S is entropy. The more negative Delta G is, the more available (or potential or “free”) energy exists in the system (e. Delta G of - 1. 00. To help with the point I really want to make I refer to you this video which does a good job explaining Gibbs free energy in the context of a biologic system. Take a moment to watch this video, if you’re not already intimately familiar with this concept. In other words, these interventions offer more potential energy (with less oxygen consumption, don’t forget, which is the really amazing part). Recall that ketones make their way onto the metabolic playing field without going through PDH. Back to the original question. Richard Veech (NIH) and Dr. Kieran Clarke (Oxford). Because the results of their work have not yet been published, I can’t comment much or share the data I have, which they shared with me. Amber January 1, 2013. I just made the suggestion that a ketogenic diet might plausibly enhance muscular growth as well as recovery (http://www.ketotic.org/2012/12. With all of the sweet stuff around this time of year! Ibotta is a free app that pays you cash for everyday purchases. Ditch the coupons and get cash back the fun and easy way. Ibotta has exclusive rebates at your. According to Kevin, it is not generally appreciated how making ketones from fatty acids affects overall energy efficiency. Nevertheless, this can be examined by comparing the enthalpy of combustion of 4. B- OHB, which is about - 2,1. Thus, there is about 2. This suggests that being in nutritional ketosis may require more overall system energy, while still increasing work potential. Target Cartwheel, a whole new spin on coupons. Find & share the best deals in all your favorite categories: grocery, baby, apparel, health & beauty & more. Save money on hundreds of brands in store or online with Coupons.com. Find printable coupons for grocery and top brands. Get verified coupon codes daily. Receive information and updates on Adweek Events, Awards, and Promotions Receive news and offers from our friends and sponsors. What's the difference between biscuits & cookies? The answer is an interesting buffet of linguistics, history, and technology. Well, frankly, I’m tired of reading so much nonsense on this topic. Everybody with a Word. Press account (and countless people without) feels entitled to spew their opinions about ketosis without even the slightest clue of what they are talking about. Next time, I’ll try to back it out of the weeds and get to more clinically interesting stuff. How I lost a stone in a week. This is a diet I was handed and told that it was designed to help people crash lose a stone for operations. Food provides energy that comes in the form of calories (or kilocalories). All foods provide calories, whether they have a nutrition label or not, and it. You can use an app on your phone or computer. Even if you don't consistently use a calorie counter, it. Knowledge is power, after all. Start by reviewing nutrition labels. If you have your phone handy you can easily search for the food. Many calorie counter apps also allow you to scan a food's barcode to easily locate its nutrition facts label. In addition to calories, labels provide valuable information about what's in your food, so it's crucial that you understand how to read them. And make sure to follow the do. The truth is that the number varies person- to- person based on age, gender, activity level, daily calories burned, and weight goals. Enter your information into a daily calorie goal calculator to find out, then use a calorie counter to track your food intake and see if you're meeting your goal. How Many Calories Are in Carbs, Proteins, Fats, and Alcohol? Some foods contain more calories than others, and it often depends on the macronutrient content of the food. In general, foods are made up of carbohydrates, proteins, and fats, each of which provide a different number of calories: Carbohydrates provide 4 calories per gram. Proteins provide 4 calories per gram. Fats provide 9 calories per gram. If you. After a few drinks, the calories in your favorite alcoholic drinks can really stack up. Make a few portion size mistakes or eat a meal too high in dietary fat and you may be consuming more calories than you realize. Are All Calories the Same? Understanding Calories vs. Quality of Diet. Does it matter where your calories come from? Is it better to get most of your calories from protein, or eat fewer calories from carbs? Experts have argued on this topic for some time, but the answer is simple: a calorie is just a calorie when it comes to counting the numbers, but the different sources of calories can have different effects on your weight because of factors like satiety and effects on hormones. Bottom line: focus on eating a healthy, balanced diet full of fruits and vegetables, whole grains, and lean proteins to get the most benefit. Are Nutrition Facts Labels Accurate? We. The numbers we see are merely estimates.
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