The Best Diet Part I

This post will be part one of a three part post series going over the controversy of the ‘best’ diet. 

You make more than 200 decisions in a day—which phone to buy, where to go for vacation, who to date. Obviously these are questions that require tons of deliberation. The general quality of your life is often determined by questions that seemingly have little significance but carry a huge consequence. How about another question that we always ask ourselves, one that has the capability to have an enormous impact or none at all?

“What is the best diet?”

Again, right? Source

Of the hundreds of decisions you make per day, approximately 226 decisions will be about food (Wansink). Due to the propensity of food decisions in your daily lives, it goes to say that such a question is riddled with endless loopholes, criticism, lies, and truth. It’s talked about so commonly that you can just shrug it off, but the importance is scarily deceiving. Most importantly, the significance of this question lies within the context of the person asking it, because certainly, the idea that a perfect diet exists to fit everyone’s wants and needs may be nothing but a false truth.

And if you work in a field that is intricately involved with human health, disease, and nutrition—like a Registered Dietitian (RD)—it’s the worst possible question.  Dealing with a question that is entangled in a web of this and that is difficult enough to write in a blog post, imagine trying to explain it to a person who has no clue. RDs deal with not luxuries people think about once every few years like buying a house or car, but a commodity, and their responses directly affect those 226 daily food decisions people make. And because this question has been asked so many times and approached in so many different ways, the significance of it is slowly beginning to lose out to the myriad of options available in the mainstream.

Wrapped up nicely with the “what is the best diet” are a couple of other multi-faceted questions that you probably want answers for sooner than your birthday.

What are the best foods to eat?”

What’s the best way to do [insert goal here]?”

So on and so forth. The best diet would be the best present ever. Although it makes sense that there is no one best diet and no one best food, these questions cannot be proven through science. If it could, then scientists would still not be spending hundreds of man hours and thousands of research grant dollars trying to figure out what the optimal diet is. Fortunately, science does shed light on the path you should take to achieve good health through diet.

For your next birthday. Source

THE MAZE OF DIETS

Follow any large media outlet and you’ll be sure to read, hear, or smell reports and journalists talking about whether you should “slash carbs to carve a sleek and sexy six-pack” or “drop pounds by dropping fat” or “eat like a caveman and look like one” (uh, do you actually want to look like this?). So much conflicting information, so little time—who to listen to?

Image result for caveman

It’s the grass-fed, organic, free-range, non-GMO, pastured limestone that helps him maintain perfect white teeth (source)

Outside of the lab, many camps have laid claim to a best diet, but no one seems to agree with each other fully. One study will come out today that refutes yesterday’s study on the same diet. On the vast intranet, you have various nutrition experts and armchair gurus going to war on their keyboards espousing their preferred diet without tickling the thought that their diet may not actually be the best. The devil is in the details, so asking a layperson to read a full article and understand the meaning of those details is like asking a dolphin to walk on land—it’s not going to happen. That’s why there’s the media to help, except they really don’t. Your best bet is to look for someone who actually reads and keeps up with the literature—say a doctor or an RD. Luckily, I do enjoy a good read and turning the knowledge of science into application is a passion of mine. Very basically, let me answer the almighty question, “which is the best diet”. And it is… <drum roll>

The Mediterranean diet.

A low-carbohydrate diet.

A vegetarian (or vegan) diet.

The Dietary Approaches to Stop Hypertension (DASH) program.

The Paleo diet.

Weight Watchers

… Hold the phone! Didn’t I just say that I would tell you what the best diet is? Why, yes, I did, and I did. I know that best is a term to denote a singular thing that is superior to all others in its respective category, but read on to find out why everything can be the best.

LET THE RESEARCH SPEAK

The topic of what diet is best is probably one of the hottest in nutrition research and a new study (and book) is published just as quickly as a baby is born. According to the research, it’s fine to contradict myself. Why? Because each diet is the best. Before we move onto why each diet can be the best, let’s look at very briefly what some of the recent research actually has to say in favor of the major dietary regimes and their spin-offs:

The Mediterranean Diet—one of the “children” from a combination of research and observation, the Mediterranean diet seeks to reflect the dietary habits of some of the healthiest people in the world. Unlike most dietary programs, the Mediterranean diet is one of the few scientifically studied that attempts to mimic what is actually consumed in observation. Specifically, the Mediterranean diet emphasizes fish, nuts, legumes, fruits, vegetables, and low glycemic carbohydrate sources. In the literature, a Mediterranean diet is similar to a moderate carbohydrate diet, about 40%. Some benefits:

  • Increased life span (Crous-Bou, 2014)
  • Decreased weight and obesity (Sayon-Orea, 2014; Huo 2014; Thomas 2007)
  • Improved non-alcoholic fatty liver disease (Zivkovic, 2007)
  • Improved hemoglobin A1c and other diabetes markers (Carter, 2014; Huo, 2014; Esposito, 2014)
  • Improved blood lipid panel (Huo, 2014; Richard 2014; Thomas, 2007)
  • Decreased risk of certain cancers (Whalen, 2014)

Low-carbohydrate diet—popularized mainstream by Robert Atkins, MD, this dietary protocol has really been in practice throughout mankind’s history. There are various societies that consume low daily carbohydrates, such as the Inuits. Because of carbohydrate’s ability to affect various health markers such as blood sugars, it is being more commonly manipulated, and with good results. Low carbohydrate diets can be characterized in the literature as anything under 40% and as low as 5% of total calories.

  • Improved satiety (Gibson, 2015; Erlanson-Albertsson, 2005)
  • Significant weight loss, even against FDA approved weight loss drugs (Yancy 2010; Yancy, 2004; Sharman, 2004; Bertoli, 2014; Tay 2008)
  • Improved blood lipid panels, especially in those with high triglycerides (Yancy, 2004; Thomson, 2010; Sharman 2004; Volek, 2008)
  • Improved diabetes markers, especially in those with compromised insulin sensitivity (Samaha, 2007; Feinman, 2015; Arora, 2005)
  • Decreased inflammation and tumor growth (especially in response to ketogenic diets)(Ho, 2014; Klement, 2011)

Low-fat diets—programs such as Dietary Approach to Stop Hypertension are those purported to improve blood lipids under the premise that saturated fat and cholesterol increase risk of heart disease and blood pressure. There is extensive evidence that free-living populations do follow a somewhat lower-fat diet and this can also include those who are vegetarian. Asian populations typically consume a diet lower in fat, for example. Fat content is usually below 30% and carbohydrates are higher, above 50%.

  • Decreased weight and obesity (Astrup, 2000; Astrup 2002; Hooper, 2012; Mueller-Cunningham, 2003; Tay, 2008)
  • Improved diabetes markers (Yokoyama, 2014)
  • Improved cardiovascular health, such as blood pressure and blood lipids (Yokoyama, 2014; Shridhar, 2014; Famodu, 1998; Nosova, 2015)
  • Improved inflammatory markers (Turner-McGrievy, 2014; Egert, 2014)
  • Improved non-alcoholic fatty liver disease (Ma, 2015)
  • Decreased risk of certain cancers (Fung, 2010)

Paleolithic diets—the attempt to emulate how our hunter-gatherer ancestors ate. “Paleo” diets have gained an immense surge of popularity since the late 1970’s when a seminal paper was produced citing anthropological data that our hunter-gatherer ancestors ate quite differently than how we are currently eating. Supporters of this program propose that by eating lean meats, vegetables, fruits, nuts, and seeds, and excluding dairy, legumes, wheat, and grains, we will see a boost in our health and performance because we will be eating concomitantly with our genetic makeup. Research does not give a clear macronutrient breakdown of a paleo diet, only that the program fits within the framework of the paleo principles mentioned above.

  • Improves weight loss and obesity (Boers, 2014; Mellberg, 2014)
  • Improves satiety (Jonsson, 2013; Jonsson, 2010)
  • Decreases risk of certain cancers (Whalen, 2014)
  • Improves cardiovascular risk factors (Jonsson, 2009; Klonoff, 2009)
  • Improves diabetes markers (Frassetto, 2009; Klonoff, 2009)
  • Improves metabolic syndrome characteristics (Boers, 2014; Lindeberg, 2012)

“THE RESEARCH HAS SPOKEN… AND I’M STILL CONFUSED”

The above is just a small handful of proposed health benefits of each diet. There are seriously hundreds of thousands of studies on each diet and their derivatives; it’s no wonder the average person has no clue where to start when it comes to which diet they should follow. I also refrained from going into the demerits of each diet because I do not want this post to be the length of half a book. Despite the small list, do you see a pattern? Here is the bottom line and the answer you have been waiting for:

Any diet will work. Any diet has the potential to be the “best diet”. And not surprisingly, each eating pattern overlaps with one another in some aspect of health, whether it’s improving diabetes, cardiovascular disease, or weight. The researchers in each study were looking at a particular end point, because frankly, it will be nearly impossible to study how each food affects each health biomarker, especially in context of individual differences. Nonetheless, each diet possessed the ability to improve health to a statistically significant degree.

Stay tuned to read how to connect the ‘best’ diet to your situation.

REFERENCES

Ajala O1English PPinkney J. Systematic review and meta-analysis of different dietary approaches to the management of type 2 diabetes. Am J Clin Nutr. 2013 Mar;97(3):505-16. doi: 10.3945/ajcn.112.042457. Epub 2013 Jan 30.

Arora SK1McFarlane SI. The case for low carbohydrate diets in diabetes management. Nutr Metab (Lond). 2005 Jul 14;2:16.

Astrup A1Astrup ABuemann BFlint ARaben A. Low-fat diets and energy balance: how does the evidence stand in 2002? Proc Nutr Soc. 2002 May;61(2):299-309.

Astrup A1Ryan LGrunwald GKStorgaard MSaris WMelanson EHill JO. The role of dietary fat in body fatness: evidence from a preliminary meta-analysis of ad libitum low-fat dietaryintervention studies. Br J Nutr. 2000 Mar;83 Suppl 1:S25-32.

Bertoli S1Trentani C2Ferraris C2De Giorgis V3Veggiotti P3Tagliabue A4. Long-term effects of a ketogenic diet on body composition and bone mineralization in GLUT-1 deficiency syndrome: a case series. Nutrition. 2014 Jun;30(6):726-8. doi: 10.1016/j.nut.2014.01.005.

Boers I1, Muskiet FA, Berkelaar E, Schut E, Penders R, Hoenderdos K, Wichers HJ, Jong MC. Favourable effects of consuming a Palaeolithic-type diet on characteristics of the metabolic syndrome: a randomized controlled pilot-study. Lipids Health Dis. 2014 Oct 11;13:160. doi: 10.1186/1476-511X-13-160.

Carter P1Achana FTroughton JGray LJKhunti KDavies MJ. A Mediterranean diet improves HbA1c but not fasting blood glucose compared to alternative dietary strategies: a network meta-analysis. J Hum Nutr Diet. 2014 Jun;27(3):280-97. doi: 10.1111/jhn.12138.

Crous-Bou M1Fung TT2Prescott J3Julin B1Du M4Sun Q5Rexrode KM6Hu FB7De Vivo I8. Mediterranean diet and telomere length in Nurses’ Health Study: population based cohort study. BMJ. 2014 Dec 2;349:g6674. doi: 10.1136/bmj.g6674.

de Almeida Ventura Dde Matos Fonseca VRamos EGMarinheiro LPde Souza RAde Miranda Chaves CRPeixoto MV. Association between quality of the diet and cardiometabolic risk factors in postmenopausal women. Nutr J. 2014 Dec 22;13(1):121.

Egert S1Baxheinrich A2Lee-Barkey YH3Tschoepe D3Wahrburg U2Stratmann B3. Effects of an energy-restricted diet rich in plant-derived α-linolenic acid on systemic inflammation and endothelial function in overweight-to-obese patients with metabolic syndrome traits. Br J Nutr. 2014 Oct 28;112(8):1315-22. doi: 10.1017/S0007114514002001.

Erlanson-Albertsson C1Mei J. The effect of low carbohydrate on energy metabolism. Int J Obes (Lond). 2005 Sep;29 Suppl 2:S26-30.

Esposito K1Maiorino MI2Petrizzo M2Bellastella G3Giugliano D3. The effects of a Mediterranean diet on the need for diabetes drugs and remission of newly diagnosed type 2 diabetes: follow-up of a randomized trial. Diabetes Care. 2014 Jul;37(7):1824-30. doi: 10.2337/dc13-2899.

Famodu AA1Osilesi OMakinde YOOsonuga OA. Blood pressure and blood lipid levels among vegetarian, semi-vegetarian, and non-vegetarian native Africans. Clin Biochem. 1998 Oct;31(7):545-9.

Feinman RD1Pogozelski WK2Astrup A3Bernstein RK4Fine EJ5Westman EC6Accurso A7Frassetto L8Gower BA9McFarlane SI10Nielsen JV11Krarup T12Saslow L13Roth KS14Vernon MC15Volek JS16Wilshire GB17Dahlqvist A18Sundberg R19Childers A20Morrison K21Manninen AH22Dashti HM23,Wood RJ24Wortman J25Worm N26. Dietary carbohydrate restriction as the first approach in diabetes management: Critical review and evidence base. Nutrition. 2015 Jan;31(1):1-13. doi: 10.1016/j.nut.2014.06.011.

Foreyt JP1Salas-Salvado JCaballero BBulló MGifford KDBautista ISerra-Majem L. Weight-reducing diets: are there any differences? Nutr Rev. 2009 May;67 Suppl 1:S99-101. doi: 10.1111/j.1753-4887.2009.00169.x.

Frassetto LA1Schloetter MMietus-Synder MMorris RC JrSebastian A. Metabolic and physiologic improvements from consuming a paleolithic, hunter-gatherer type diet. Eur J Clin Nutr. 2009 Aug;63(8):947-55. doi: 10.1038/ejcn.2009.4.

Fung TT1Hu FBWu KChiuve SEFuchs CSGiovannucci E. The Mediterranean and Dietary Approaches to Stop Hypertension (DASH) diets and colorectal cancer. Am J Clin Nutr. 2010 Dec;92(6):1429-35. doi: 10.3945/ajcn.2010.29242.

Gardner CD1Kiazand AAlhassan SKim SStafford RSBalise RRKraemer HCKing AC. Comparison of the Atkins, Zone, Ornish, and LEARN diets for change in weight and related risk factors among overweight premenopausal women: the A TO Z Weight Loss Study: a randomized trial. JAMA. 2007 Mar 7;297(9):969-77.

Gibson AA1Seimon RVLee CMAyre JFranklin JMarkovic TPCaterson IDSainsbury A. Do ketogenic diets really suppress appetite? A systematic review and meta-analysis. Obes Rev. 2015 Jan;16(1):64-76. doi: 10.1111/obr.12230.

Hession M1, Rolland C, Kulkarni U, Wise A, Broom J. Systematic review of randomized controlled trials of low-carbohydrate vs. low-fat/low-calorie diets in the management of obesity and its comorbidities. Obes Rev. 2009 Jan;10(1):36-50. doi: 10.1111/j.1467-789X.2008.00518.x.

Ho VW1Leung KHsu ALuk BLai JShen SYMinchinton AIWaterhouse DBally MBLin WNelson BHSly LMKrystal G. A low carbohydrate, high protein diet slows tumor growth and prevents cancer initiation. Cancer Res. 2011 Jul 1;71(13):4484-93. doi: 10.1158/0008-5472.CAN-10-3973.

Hooper L1Abdelhamid AMoore HJDouthwaite WSkeaff CMSummerbell CD. Effect of reducing total fat intake on body weight: systematic review and meta-analysis of randomised controlled trials and cohort studies. BMJ. 2012 Dec 6;345:e7666. doi: 10.1136/bmj.e7666.

Hu T1Mills KTYao LDemanelis KEloustaz MYancy WS JrKelly TNHe JBazzano LA. Effects of low-carbohydrate diets versus low-fat diets on metabolic risk factors: a meta-analysis of randomized controlled clinical trials. Am J Epidemiol. 2012 Oct 1;176 Suppl 7:S44-54. doi: 10.1093/aje/kws264.

Huo R1Du T2Xu Y2Xu W2Chen X2Sun K3Yu X2. Effects of Mediterranean-style diet on glycemic control, weight loss and cardiovascular risk factors among type 2 diabetes individuals: a meta-analysis. Eur J Clin Nutr. 2014 Nov 5. doi: 10.1038/ejcn.2014.243.

Jönsson T1, Granfeldt Y, Ahrén B, Branell UC, Pålsson G, Hansson A, Söderström M, Lindeberg S. Beneficial effects of a Paleolithic diet on cardiovascular risk factors in type 2 diabetes: a randomized cross-over pilot study. Cardiovasc Diabetol. 2009 Jul 16;8:35. doi: 10.1186/1475-2840-8-35.

Jönsson T1, Granfeldt Y, Lindeberg S, Hallberg AC. Subjective satiety and other experiences of a Paleolithic diet compared to a diabetes diet in patients with type 2 diabetes. Nutr J. 2013 Jul 29;12:105. doi: 10.1186/1475-2891-12-105.

Jönsson T1Granfeldt YErlanson-Albertsson CAhrén BLindeberg S. A paleolithic diet is more satiating per calorie than a mediterranean-like diet in individuals with ischemic heart disease. Nutr Metab (Lond). 2010 Nov 30;7:85. doi: 10.1186/1743-7075-7-85.

Klement RJ1Kämmerer U. Is there a role for carbohydrate restriction in the treatment and prevention of cancer? Nutr Metab (Lond). 2011 Oct 26;8:75. doi: 10.1186/1743-7075-8-75.

Klonoff DC. The beneficial effects of a Paleolithic diet on type 2 diabetes and other risk factors for cardiovascular disease. J Diabetes Sci Technol. 2009 Nov 1;3(6):1229-32.

Lindeberg S1. Paleolithic diets as a model for prevention and treatment of Western disease. Am J Hum Biol. 2012 Mar-Apr;24(2):110-5. doi: 10.1002/ajhb.22218.

Ma H1You GP2Cui F1Chen LF1Yang XJ1Chen LG3Lu HD4Zhang WQ1. Effects of a low-fat diet on the hepatic expression of adiponectin and its receptors in rats with NAFLD. Ann Hepatol. 2015 Jan-Feb;14(1):108-17.

McClain ADOtten JJHekler EBGardner CD. Adherence to a low-fat vs. low-carbohydrate diet differs by insulin resistance status. Diabetes Obes Metab. 2013 Jan;15(1):87-90. doi: 10.1111/j.1463-1326.2012.01668.x. Epub 2012 Aug 22.

McMillan-Price J1, Petocz P, Atkinson F, O’neill K, Samman S, Steinbeck K, Caterson I, Brand-Miller J. Comparison of 4 diets of varying glycemic load on weight loss and cardiovascular risk reduction in overweight and obese young adults: a randomized controlled trial. Arch Intern Med. 2006 Jul 24;166(14):1466-75.

Mellberg C1, Sandberg S2, Ryberg M1, Eriksson M3, Brage S4, Larsson C5, Olsson T1, Lindahl B2. Long-term effects of a Palaeolithic-type diet in obese postmenopausal women: a 2-year randomized trial. Eur J Clin Nutr. 2014 Mar;68(3):350-7. doi: 10.1038/ejcn.2013.290. Epub 2014 Jan 29.

Mueller-Cunningham WM1Quintana RKasim-Karakas SE. An ad libitum, very low-fat diet results in weight loss and changes in nutrient intakes in postmenopausal women. J Am Diet Assoc. 2003 Dec;103(12):1600-6.

Naude CE1, Schoonees A1, Senekal M2, Young T3, Garner P4, Volmink J3. Low carbohydrate versus isoenergetic balanced diets for reducing weight and cardiovascular risk: a systematic review and meta-analysis. PLoS One. 2014 Jul 9;9(7):e100652. doi: 10.1371/journal.pone.0100652. eCollection 2014.

Nordmann AJ1, Nordmann A, Briel M, Keller U, Yancy WS Jr, Brehm BJ, Bucher HC. Effects of low-carbohydrate vs low-fat diets on weight loss and cardiovascular risk factors: a meta-analysis of randomized controlled trials. Arch Intern Med. 2006 Feb 13;166(3):285-93.

Nosova EV1Conte MS2Grenon SM3. Advancing beyond the “heart-healthy diet” for peripheral arterial disease. J Vasc Surg. 2015 Jan;61(1):265-274. doi: 10.1016/j.jvs.2014.10.022.

Richard C1Couture PDesroches SNehmé BBourassa SDroit ALamarche B. Effect of an isoenergetic traditional Mediterranean diet on the high-density lipoprotein proteome in men with the metabolic syndrome. J Nutrigenet Nutrigenomics. 2014;7(1):48-60. doi: 10.1159/000363137. Epub 2014 Jul 4.

Sayón-Orea C1Santiago SCuervo MMartínez-González MAGarcia AMartínez JA. Adherence to Mediterranean dietary pattern and menopausal symptoms in relation to overweight/obesity in Spanish perimenopausal and postmenopausal women. Menopause. 2014 Dec 15.

Schwab U1Lauritzen L2Tholstrup T2Haldorssoni T3Riserus U4Uusitupa M5Becker W6. Effect of the amount and type of dietary fat on cardiometabolic risk factors and risk of developing type 2 diabetes, cardiovascular diseases, and cancer: a systematic review. Food Nutr Res. 2014 Jul 10;58. doi: 10.3402/fnr.v58.25145.

Schwingshackl L, Hoffmann G. Comparison of effects of long-term low-fat vs high-fat diets on blood lipid levels in overweight or obese patients: a systematic review and meta-analysis. J Acad Nutr Diet. 2013 Dec;113(12):1640-61. doi: 10.1016/j.jand.2013.07.010. Epub 2013 Oct 17.

Sharman MJ1Gómez ALKraemer WJVolek JS. Very low-carbohydrate and low-fat diets affect fasting lipids and postprandial lipemia differently in overweight men. J Nutr. 2004 Apr;134(4):880-5.

Shridhar K1Dhillon PK1Bowen L2Kinra S2Bharathi AV3Prabhakaran D4Reddy KS5Ebrahim S2Indian Migration Study Group. The association between a vegetarian diet and cardiovascular disease (CVD) risk factors in India: the Indian Migration Study. PLoS One. 2014 Oct 24;9(10):e110586. doi: 10.1371/journal.pone.0110586.

Siebenhofer A1Jeitler KBerghold AWaltering AHemkens LGSemlitsch TPachler CStrametz RHorvath K. Long-term effects of weight-reducing diets in hypertensive patients. Cochrane Database Syst Rev. 2011 Sep 7;(9):CD008274. doi: 10.1002/14651858.CD008274.pub2.

Tay J1Brinkworth GDNoakes MKeogh JClifton PM. Metabolic effects of weight loss on a very-low-carbohydrate diet compared with an isocaloric high-carbohydrate diet in abdominally obese subjects. J Am Coll Cardiol. 2008 Jan 1;51(1):59-67. doi: 10.1016/j.jacc.2007.08.050.

Thomas DE1Elliott EJBaur L. Low glycaemic index or low glycaemic load diets for overweight and obesity. Cochrane Database Syst Rev. 2007 Jul 18;(3):CD005105.

Thomson CA1Stopeck ATBea JWCussler ENardi EFrey GThompson PA. Changes in body weight and metabolic indexes in overweight breast cancer survivors enrolled in a randomized trial of low-fat vs. reduced carbohydrate diets. Nutr Cancer. 2010;62(8):1142-52. doi: 10.1080/01635581.2010.513803.

Turner-McGrievy GM1Wirth MD2Shivappa N2Wingard EE3Fayad R3Wilcox S3Frongillo EA4Hébert JR2. Randomization to plant-based dietary approaches leads to larger short-term improvements in Dietary Inflammatory Index scores and macronutrient intake compared with diets that contain meat. Nutr Res. 2014 Dec 3. pii: S0271-5317(14)00267-X. doi: 10.1016/j.nutres.2014.11.007.

Volek JS1Fernandez MLFeinman RDPhinney SD. Dietary carbohydrate restriction induces a unique metabolic state positively affecting atherogenic dyslipidemia, fatty acid partitioning, and metabolic syndrome. Prog Lipid Res. 2008 Sep;47(5):307-18. doi: 10.1016/j.plipres.2008.02.003.

Wansink, Brian and Jeffrey Sobal (2007), “Mindless Eating: The 200 Daily Food Decisions We Overlook,” Environment and Behavior 39:1, 106-123

Whalen KAMcCullough MFlanders WDHartman TJJudd SBostick RM. Paleolithic and mediterranean diet pattern scores and risk of incident, sporadic colorectal adenomas. Am J Epidemiol. 2014 Dec 1;180(11):1088-97. doi: 10.1093/aje/kwu235.

Yancy WS Jr1Olsen MKGuyton JRBakst RPWestman EC. A low-carbohydrate, ketogenic diet versus a low-fat diet to treat obesity and hyperlipidemia: a randomized, controlled trial. Ann Intern Med. 2004 May 18;140(10):769-77.

Yancy WS Jr1Westman ECMcDuffie JRGrambow SCJeffreys ASBolton JChalecki AOddone EZ. A randomized trial of a low-carbohydrate diet vs orlistat plus a low-fat diet for weight loss. Arch Intern Med. 2010 Jan 25;170(2):136-45. doi: 10.1001/archinternmed.2009.492.

Yokoyama Y1Barnard ND1Levin SM1Watanabe M1. Vegetarian diets and glycemic control in diabetes: a systematic review and meta-analysis. Cardiovasc Diagn Ther. 2014 Oct;4(5):373-82. doi: 10.3978/j.issn.2223-3652.2014.10.04.

Yokoyama Y1Nishimura K2Barnard ND3Takegami M4Watanabe M5Sekikawa A6Okamura T7Miyamoto Y8. Vegetarian diets and blood pressure: a meta-analysis. JAMA Intern Med. 2014 Apr;174(4):577-87. doi: 10.1001/jamainternmed.2013.14547.

Zivkovic AM1German JBSanyal AJ. Comparative review of diets for the metabolic syndrome: implications for nonalcoholic fatty liver disease. Am J Clin Nutr. 2007 Aug;86(2):285-300.