{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,14]],"date-time":"2026-10-14T01:56:08Z","timestamp":1791942968805,"version":"4.3.4"},"reference-count":57,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2021,3,24]],"date-time":"2021-03-24T00:00:00Z","timestamp":1616544000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Nutr."],"abstract":"<jats:p><jats:bold>Background:<\/jats:bold> Ketogenic diets (<jats:bold>KDs<\/jats:bold>) that elevate beta-hydroxybutyrate (<jats:bold>BHB<\/jats:bold>) promote weight and fat loss. Exogenous ketones, such as ketone salts (<jats:bold>KS<\/jats:bold>), also elevate BHB concentrations with the potential to protect against muscle loss during caloric restriction. Whether augmenting ketosis with KS impacts body composition responses to a well-formulated KD remains unknown.<\/jats:p><jats:p><jats:bold>Purpose:<\/jats:bold> To explore the effects of energy-matched, hypocaloric KD feeding (&amp;lt;50 g carbohydrates\/day; 1.5 g\/kg\/day protein), with and without the inclusion of KS, on weight loss and body composition responses.<\/jats:p><jats:p><jats:bold>Methods:<\/jats:bold> Overweight and obese adults were provided a precisely defined hypocaloric KD (~75% of energy expenditure) for 6 weeks. In a double-blind manner, subjects were randomly assigned to receive ~24 g\/day of a racemic BHB-salt (KD + KS; <jats:italic>n<\/jats:italic> = 12) or placebo (KD + PL; <jats:italic>n<\/jats:italic> = 13). A matched comparison group (<jats:italic>n<\/jats:italic> = 12) was separately assigned to an isoenergetic\/isonitrogenous low-fat diet (LFD). Body composition parameters were assessed by dual x-ray absorptiometry and magnetic resonance imaging.<\/jats:p><jats:p><jats:bold>Results:<\/jats:bold> The KD induced nutritional ketosis (&amp;gt;1.0 mM capillary BHB) throughout the study (<jats:italic>p<\/jats:italic> &amp;lt; 0.001), with higher fasting concentrations observed in KD + KS than KD + PL for the first 2 weeks (<jats:italic>p<\/jats:italic> &amp;lt; 0.05). There were decreases in body mass, whole body fat and lean mass, mid-thigh muscle cross-sectional area, and both visceral and subcutaneous adipose tissues (<jats:italic>p<\/jats:italic> &amp;lt; 0.001), but no group differences between the two KDs or with the LFD. Urine nitrogen excretion was significantly higher in KD + PL than LFD (<jats:italic>p<\/jats:italic> &amp;lt; 0.01) and trended higher in KD + PL compared to KD + KS (<jats:italic>p<\/jats:italic> = 0.076), whereas the nitrogen excretion during KD + KS was similar to LFD (<jats:italic>p<\/jats:italic> &amp;gt; 0.05).<\/jats:p><jats:p><jats:bold>Conclusion:<\/jats:bold> Energy-matched hypocaloric ketogenic diets favorably affected body composition but were not further impacted by administration of an exogenous BHB-salt that augmented ketosis. The trend for less nitrogen loss with the BHB-salt, if manifested over a longer period of time, may contribute to preserved lean mass.<\/jats:p>","DOI":"10.3389\/fnut.2021.618520","type":"journal-article","created":{"date-parts":[[2021,3,24]],"date-time":"2021-03-24T04:49:28Z","timestamp":1616561368000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":38,"title":["The Effects of a 6-Week Controlled, Hypocaloric Ketogenic Diet, With and Without Exogenous Ketone Salts, on Body Composition Responses"],"prefix":"10.3389","volume":"8","author":[{"given":"Alex","family":"Buga","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Madison L.","family":"Kackley","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christopher D.","family":"Crabtree","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Teryn N.","family":"Sapper","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lauren","family":"Mccabe","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Brandon","family":"Fell","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rich A.","family":"LaFountain","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Parker N.","family":"Hyde","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emily R.","family":"Martini","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jessica","family":"Bowman","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yue","family":"Pan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Debbie","family":"Scandling","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Milene L.","family":"Brownlow","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Annalouise","family":"O'Connor","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Orlando P.","family":"Simonetti","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"William J.","family":"Kraemer","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jeff S.","family":"Volek","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2021,3,24]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"e0139817","DOI":"10.1371\/journal.pone.0139817","article-title":"Dietary intervention for overweight and obese adults: comparison of low-carbohydrate and low-fat diets. 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