Methods and Results: In the first study, 15 participants consumed KE or KS drinks that delivered ~12 or ~24 g of βHB. Both drinks elevated blood D-βHB concentrations (D-βHB Cmax: KE 2.8 mM, KS 1.0 mM, P < 0.001), which returned to baseline within 3–4 h. KS drinks were found to contain 50% of the L-βHB isoform, which remained elevated in blood for over 8 h, but was not detectable after 24 h. Urinary excretion of both D-βHB and L-βHB was <1.5% of the total βHB ingested and was in proportion to the blood AUC. D-βHB, but not L-βHB, was slowly converted to breath acetone. The KE drink decreased blood pH by 0.10 and the KS drink increased urinary pH from 5.7 to 8.5. In the second study, the effect of a meal before a KE drink on blood D-βHB concentrations was determined in 16 participants. Food lowered blood D-βHB Cmax by 33% (Fed 2.2 mM, Fasted 3.3 mM, P < 0.001), but did not alter acetoacetate or breath acetone concentrations. All ketone drinks lowered blood glucose, free fatty acid and triglyceride concentrations, and had similar effects on blood electrolytes, which remained normal. In the final study, participants were given KE over 9 h as three drinks (n = 12) or a continuous nasogastric infusion (n = 4) to maintain blood D-βHB concentrations greater than 1 mM. Both drinks and infusions gave identical D-βHB AUC of 1.3–1.4 moles.min.
Ketosis supplements made in poor quality, have proven to lead to side-effects such as constipation and increased levels of cholesterol and triglycerides in men, and women may also experience amenorrhea or other disruptions to the menstrual cycle. This is why it is really important to know what combination of compounds you are consuming, particularly while you are on this very strict diet because the wrong balance can really mess with you in the long term and won't give you the high performance that you are looking for.
Recently, two published studies investigated the effects of ketone salts in athletes (total n = 22).8,9 Performance over a four-minute cycling time-trial and a 150 kJ ( ~11 mins) cycling time trial were compared between ketone salts vs. carbohydrate. In the four-minute trial there was no change in performance, and in the 150 kJ test, performance decreased by 7%. Blood BHB levels peaked at 0.6 and 0.8 mM in these studies.
Ketones are also a cleaner-burning fuel than carbs. They’re burned for energy in the mitochondria, and fewer free radicals (a highly-reactive, short-lived uncharged molecule) are generated when compared to burning glucose.15 What’s more, ketone molecules themselves cause a decrease in production of free radicals,21,22 while also increasing glutathione–a powerful antioxidant protecting against mitochondrial damage induced by free radicals.23
Meanwhile Brinkworth, et al., in their 2009 paper "Long-term Effects of a Very Low-Carbohydrate Diet and a Low-Fat Diet on Mood and Cognitive Function" looked at the effects on ketogenic diet on cognitive function and mood. The study participants ate a ketogenic diet for a year and the researchers found that mood levels decreased when compared to a group eating a high carb/low fat diet. They go on to remark “there was no evidence that the dietary macronutrient composition of LC and LF diets affected cognitive functioning over the long term, as changes in cognitive function were similar for both diets”.
Humans in the hunter-gatherer era survived thanks to metabolic flexibility — the body’s ability to use different fuels for energy depending on the nutrients available. This adaptation was vital during a time when the source, quantity, and frequency of food was uncertain[*]. Most of the time, people were fasting, so their bodies ran on ketones, not glucose.
Affiliate Disclosure: There are links on this site that can be defined as affiliate links. This means that I may receive a small commission (at no cost to you) if you purchase something when clicking on the links that take you through to a different website. By clicking on the links, you are in no way obligated to buy.
Medical Disclaimer: The material on this site is provided for informational purposes only and is not medical advice. Always consult your physician before beginning any diet or exercise program.
Copyright © lowcarbtransformation.com