Transcript a low-protein and high-glycemic-index diet

Journal Club
Larsen TM, Dalskov SM, van Baak M, Jebb SA, Papadaki A, Pfeiffer AF, Martinez
JA, Handjieva-Darlenska T, Kunešová M, Pihlsgård M, Stender S, Holst C, Saris
WH, Astrup A; Diet, Obesity, and Genes (Diogenes) Project.
Diets with high or low protein content and glycemic index for weight-loss
maintenance.
N Engl J Med. 2010 Nov 25;363(22):2102-13.
Church TS, Blair SN, Cocreham S, Johannsen N, Johnson W, Kramer K, Mikus
CR, Myers V, Nauta M, Rodarte RQ, Sparks L, Thompson A, Earnest CP.
Effects of aerobic and resistance training on hemoglobin A1c levels in patients
with type 2 diabetes: a randomized controlled trial.
JAMA. 2010 Nov 24;304(20):2253-62.
2010年12月2日 8:30-8:55
８階 医局
埼玉医科大学 総合医療センター 内分泌・糖尿病内科
Department of Endocrinology and Diabetes,
Saitama Medical Center, Saitama Medical University
松田 昌文
Matsuda, Masafumi
From the Department of Nutrition, Harvard School of Public Health (F.M.S., L.M.B.); the Channing
Laboratory (F.M.S., V.J.C., N.L.) and the Endocrine Division (M.S.L.), Department of Medicine, Brigham
and Women’s Hospital and Harvard Medical School; and the Department of Nutrition, Brigham and
Women’s Hospital (K.M.) — all in Boston; Pennington Biomedical Research Center of the Louisiana State
University System, Baton Rouge (G.A.B., S.R.S., D.H.R., S.D.A., C.M.C., J.C.R., L.J., F.L.G., D.A.W.); and
the National Heart, Lung, and Blood Institute, Bethesda, MD (C.M.L., E.O.).
Mean Changes in Body Weight and Waist Circumference at Various Time Points
http://www.atkins.com/
The glycemic index, glycaemic index, or GI is a measure of the
effects of carbohydrates on blood sugar levels. Carbohydrates
that break down quickly during digestion and release glucose
rapidly into the bloodstream have a high GI; carbohydrates that
break down more slowly, releasing glucose more gradually into
the bloodstream, have a low GI. The concept was developed by
Dr. David J. Jenkins and colleagues in 1980–1981 at the
University of Toronto in their research to find out which foods
were best for people with diabetes.
The insulin index is also useful, as it provides a direct measure
of the insulin response to a food.
The glycemic index of a food is defined as the area under the
two hour blood glucose response curve (AUC) following the
ingestion of a fixed portion of carbohydrate (usually 50 g). The
AUC of the test food is divided by the AUC of the standard
(either glucose or white bread, giving two different definitions)
and multiplied by 100. The average GI value is calculated from
data collected in 10 human subjects. Both the standard and test
food must contain an equal amount of available carbohydrate.
The result gives a relative ranking for each tested food.
Classification
GI range
Examples
Low GI
55 or less
most fruits and vegetables, legumes/pulses, whole grains,
meat, eggs, milk, nuts, fructose and products low in
carbohydrates
Medium GI
56–69
whole wheat products, basmati rice, sweet potato, sucrose
High GI
70 and above
baked potatoes, watermelon, white bread, most white rices,
corn flakes, extruded breakfast cereals, glucose
the Department of Human Nutrition, Faculty of Life Sciences (T.M.L., S.-M.D., A.A.), and the Department of Clinical Biochemistry, Gentofte
Hospital (S.S.), University of Copenhagen; and the Institute of Preventive Medicine, Copenhagen University Hospital (M.P., C.H.) — all in
Copenhagen; the NUTRIM (Nutrition and Toxicology Research Institute Maastricht) School for Nutrition, Toxicology and Metabolism, Department
of Human Biology, Maastricht University Medical Centre, Maastricht, the Netherlands (M.B., W.H.M.S.); the Medical Research Council Human
Nutrition Research, Elsie Widdowson Laboratory, Cambridge, United Kingdom (S.A.J.); the Department of Social Medicine, Preventive Medicine,
and Nutrition Clinic, University of Crete, Heraklion, Crete, Greece (A.P.); the Department of Clinical Nutrition, German Institute of Human Nutrition
Potsdam-Rehbrücke, Nuthetal, Germany (A.F.H.P.); the Department of Endocrinology, Diabetes, and Nutrition, Charité Universitätsmedizin
Berlin, Berlin (A.F.H.P.); the Department of Physiology and Nutrition, University of Navarra, Pamplona, Spain ( J.A.M.); the Department of
Pharmacology and Toxicology, Medical Faculty, National Transport Hospital, Sofia, Bulgaria (T.H.-D.); and the Obesity Management Center,
Institute of Endocrinology, Prague, Czech Republic (M.K.)
N Engl J Med 2010;363:2102-13.
BACKGROUND
Studies of weight-control diets that are
high in protein or low in glycemic index
have reached varied conclusions,
probably owing to the fact that the
studies had insufficient power.
METHODS
We enrolled overweight adults from eight European
countries who had lost at least 8% of their initial body
weight with a 3.3-MJ (800-kcal) low-calorie diet.
Participants were randomly assigned, in a two-by-two
factorial design, to one of five ad libitum diets to prevent
weight regain over a 26-week period: a low-protein and
low-glycemicindex diet, a low-protein and highglycemic-index diet, a high-protein and low glycemicindex diet, a high-protein and high-glycemic-index diet,
or a control diet.
Families that included at least one healthy child between 5 and 17 years of age and at
least one parent between 18 and 65 years of age who was overweight or obese
(body-mass index [the weight in kilograms divided by the square of the height in
meters] of at least 27 and less than 45)
Figure 1. Screening,
Randomization, and
Follow-up of Study
Participants.
HGI denotes high
glycemic index,
HP high protein,
LCD low-calorie diet,
LGI low glycemic index,
LP low protein.
RESULTS
A total of 1209 adults were screened (mean age, 41 years; body-mass index
[the weight in kilograms divided by the square of the height in meters], 34), of
whom 938 entered the low-calorie-diet phase of the study. A total of 773
participants who completed that phase were randomly assigned to one of the
five maintenance diets; 548 completed the intervention (71%). Fewer
participants in the high-protein and the low glycemic- index groups than in the
low-protein–high-glycemic-index group dropped out of the study (26.4% and
25.6%, respectively, vs. 37.4%; P = 0.02 and P = 0.01 for the respective
comparisons). The mean initial weight loss with the low-calorie diet was 11.0
kg. In the analysis of participants who completed the study, only the low
protein– high-glycemic-index diet was associated with subsequent significant
weight regain (1.67 kg; 95% confidence interval [CI], 0.48 to 2.87). In an
intention-to-treat analysis, the weight regain was 0.93 kg less (95% CI, 0.31 to
1.55) in the groups assigned to a high-protein diet than in those assigned to a
low-protein diet (P = 0.003) and 0.95 kg less (95% CI, 0.33 to 1.57) in the
groups assigned to a low-glycemic-index diet than in those assigned to a highglycemic-index diet (P = 0.003). The analysis involving participants who
completed the intervention produced similar results. The groups did not differ
significantly with respect to diet-related adverse events.
CONCLUSIONS
In this large European study, a modest
increase in protein content and a modest
reduction in the glycemic index led to an
improvement in study completion and
maintenance of weight loss.
(Funded by the European Commission; ClinicalTrials.gov number, NCT00390637.)
The mechanisms relating glycemic response to the regulation of body weight have
been examined in controlled feeding studies. Meals with a low glycemic index or
glycemic load elicit acute hormonal and metabolic changes that may decrease
hunger and energy intake. During weight loss, a reduction in glycemic load may
attenuate the decline in resting energy expenditure that is thought to promote weight
regain. Recently, a meta-analysis indicated that diets in which there was a reduction
in the glycemic index produced moderately more weight loss than control diets,
although the quality of the clinical trials has been limited by their small size, a failure
to show adherence to treatment, and confounding.
The glycemic response to carbohydrates is lowered when protein is ingested
simultaneously, since protein delays gastric emptying and stimulates insulin
secretion. Protein also displaces carbohydrates, as opposed to fat, from the diet
because foods high in protein are also typically high in fat. Therefore, higher-protein
diets tend to have a reduced glycemic load and might promote weight loss, at least
in part, through the mechanisms discussed above.
Several recent clinical trials have shown no significant
difference in weight loss among various popular diets,
leading to the notion that dietary composition is less
important than adherence to a diet, whatever it might be.
However, this conclusion does not consider the
fundamental relationship between psychology and
physiology. A person’s ability to maintain adherence over
time may be influenced by the way in which a diet affects
hunger and metabolism. Additional research is needed to
clarify the mechanisms by which dietary composition
regulates body weight and to devise novel strategies to
effect behavioral changes.
Message/Comments
食事療法について
らの観察。
体重維持という観点か
「蛋白多め、GIは低め」がよいそうである。
減量には、赤身肉や低脂肪の乳製品、豆類を積極的に摂り、高たんぱく質食を心がけることと、白パンや白米のように精
製度の高い炭水化物由来のエネルギーを控えること。これを守れば、面倒なカロリー計算をすることなくお腹いっぱい食
べても太らない―デンマーク・コペンハーゲン大学の研究者による世界最大規模の、食事の介入研究の結果から。
この研究は、ヨーロッパ8カ国の772世帯の成人938人と未成年827人を対象に行なわれた。
【成人の研究】
肥満の被験者（平均BMI：34）は1日800kcalの低脂肪食を8週間続け、体重が平均11kg減少した。
この実験を通過した773人はその後無作為に分けられ、半年の間次の5種類のいずれかの食事を摂取した。
１.低たんぱく質・高GI食群（たんぱく質エネルギー比13%）
２.低たんぱく質・低GI食群
３.高たんぱく質・低GI食群（たんぱく質エネルギー比25%）
４.高たんぱく質・高GI食群
５.コントロール群（現在のヨーロッパの食事摂取基準に基づくが、GI値は特別な考慮無し）
被験者のうち完了者は71%で、5群のうちどれが最も減量に向くかを調べたところ、高たんぱく質・低GI食群が効果的で、
しかも脱落者も少ないという結果が得られた。
リバウンドは参加者全員の平均で0.5kgだったが、高たんぱく質・低GI群は低たんぱく質・高GI群に比べて増加量が少な
かった。
【未成年の研究】
子どもたちには、研究に参加した親と同様の食事を摂ってもらい、ダイエットやカロリー計算などはしなかった。
被験者のうち45%が過体重だったが、このうち高たんぱく質・低GI群では15%の子どもが普通体重に変化した。
これらの結果より、ヨーロッパの食事摂取基準は、過体重の人が減量するのに適しているとはいえないとのこと。
なお、この研究でいう低GIとは55以下と定義されている。
the HART-D study
Pennington Biomedical Research Center, Louisiana State
University System, Baton Rouge (Drs Church, Johannsen,
Johnson, Myers, and Earnest; Mss Cocreham, Kramer,
Nauta, and Thompson; and Mr Rodarte); Arnold School of
Public Health, University of South Carolina, Columbia (Dr
Blair); Department of Nutrition and Exercise Physiology,
University of Missouri, Columbia (Ms Mikus); and
Department of Human Biology, NUTRIM School for
Nutrition, Toxicology and Metabolism,Maastricht University
Medical Centre, Maastricht, the Netherlands (Dr Sparks).
JAMA. 2010;304(20):2253-2262
Context Exercise guidelines for individuals with
diabetes include both aerobic and resistance
training although few studies have directly
examined this exercise combination.
Objective To examine the benefits of aerobic
training alone, resistance training alone, and a
combination of both on hemoglobin A1c (HbA1c)
in individuals with type 2 diabetes.
Design, Setting, and Participants A randomized
controlled trial in which 262 sedentary men and women
in Louisiana with type 2 diabetes and HbA1c levels of
6.5% or higher were enrolled in the 9-month exercise
program between April 2007 and August 2009.
Intervention Forty-one participants were assigned to
the non exercise control group, 73 to resistance training
3 days a week, 72 to aerobic exercise in which they
expended 12 kcal/kg per week; and 76 to combined
aerobic and resistance training in which they expended
10 kcal/kg per week and engaged in resistance training
twice a week.
Main Outcome Change in HbA1c level. Secondary
outcomes included measures of anthropometry and
fitness.
Figure 1. Participant Flow Chart
Results The study included 63.0% women and 47.3% nonwhite
participants who were a mean (SD) age of 55.8 years (8.7 years)
with a baseline HbA1c level of 7.7% (1.0%). Compared with the
control group, the absolute mean change in HbA1c in the
combination training exercise group was −0.34% (95%
confidence interval [CI], −0.64% to −0.03%; P=.03). The mean
changes in HbA1c were not statistically significant in either the
resistance training (−0.16%; 95% CI, −0.46% to 0.15%; P=.32) or
the aerobic (−0.24%; 95% CI, −0.55% to 0.07%; P=.14) groups
compared with the control group. Only the combination exercise
group improved maximum oxygen consumption (mean, 1.0
mL/kg per min; 95% CI, 0.5-1.5, P<.05) compared with the
control group. All exercise groups reduced waist circumference
from −1.9 to −2.8 cm compared with the control group. The
resistance training group lost a mean of −1.4 kg fat mass (95% CI,
−2.0 to −0.7 kg; P<.05) and combination training group lost a
mean of −1.7 (−2.3 to −1.1 kg; P<.05) compared with the control
group.
Conclusions Among patients with
type 2 diabetes mellitus, a combination
of aerobic and resistance training
compared with the non exercise
control group improved HbA1c levels.
This was not achieved by aerobic or
resistance training alone.
Trial Registration clinicaltrials.gov
Identifier: NCT00458133
Message/Comments
２型糖尿病患者で血糖を低下させる運動療
法としては 有酸素運動と抗抵抗運動の組
み合わせがよい。
有酸素性運動とレジスタンス運動の組み合わせが2型糖尿病患者の血糖レベルを、運動を行わない場合に比べて有益に改善することが出来
たという研究。改善の程度は有酸素性運動のみ、レジスタンス運動のみを行った場合には見られないものであったようだ。米国医学会誌上に
11月24日付けで発表されている。
定期的な運動が2型糖尿病患者の健康に有益な効果をもたらすことについては、これまでも多くの研究から指摘されてきており、広く受け入れ
られている。しかしながら、どのような運動様式が有益であるのか、という事については理解されてこなかった。2008年に発表された連邦政府
の身体運動ガイドラインでは、有酸素性運動とレジスタンス運動をともに実施することが推奨されていたが、運動時間をこれらの様式の運動を
組み合わせて行うべきなのか、それぞれ別個に行うべきなのかという疑問に対する明確な回答や処方箋はあらわされていなかった。
ルイジアナ州立大学の研究者ティモシー･S･チャーチ博士らは、この疑問に答を出すためにHART-D試験を実施した。本研究では262人の座
業中心の生活を送っている2型糖尿病患者を対象に、有酸素性トレーニング、レジスタンストレーニング、それらのトレーニングの組み合わせ
を処方して、血液中のヘモグロビンA1c(HbA1c)濃度の変化を検討した。HbA1cはヘモグロビンの微量成分で、血糖が結びつき機能するもの
である。HbA1cはその特性から、糖尿病のモニターとコントロールに用いられることの多い生体指標だ。
本研究の被験者の63%は女性であり、47.3%は非白人、平均年齢は56歳であった。研究開始時のHbA1cレベルは平均7.7%、糖尿病と診断
されてからは平均7.1年が経過していた。これらの被験者は、2007年の4月から8月にかけて9ヶ月間の運動プログラムに割り当てられ、41人
が運動を行わない対照群、73人がレジスタンス運動のみ、72人が有酸素性運動のみ、そして残りの76人が有酸素性運動とレジスタンス運動
を組み合わせて行う群として介入を受けた。
研究者らは、HbA1cレベルの有意な変化が対照群に比べて組み合わせ運動群において-0.34%という値で見られたことを報告している。レジ
スタンス運動のみでは-0.16%、有酸素性運動のみでは-0.24%であり、対照群に比べて有意な減少とはいえなかった。また降血糖薬の処方
は対照群で39%増加、同じくレジスタンス運動群で32%、有酸素性運動群で22%、組み合わせトレーニング群で18%、それぞれ増加した。
組み合わせ介入を行った場合のみ、対照群に比べて最大酸素消費量が改善された。また腹部周囲径については運動を行った3群全てにお
いて、対照群に比べて0.75インチから1.1インチ(1.9～2.8cm)減少した。また体脂肪量は対照群に比べてレジスタンス運動群で平均3.1ポンド
(1.4kg)減少、組み合わせ介入群では平均3.7ポンド(1.67kg)の減少が見られた。
2型糖尿病患者の無作為化試験として行われた本研究において、レジスタンスおよび有酸素性トレーニング双方が有益である可能性を示唆
し、またこの二つの様式の組み合わせを行った場合においてのみHbA1cレベルの低下が見られたことが指摘されている。更に、HbA1cレベ
ルの組み合わせ介入群と対照群における差異は、フォローアップ期間において、対照群が血糖降下薬の利用が増大し、組み合わせ介入群
での投薬が少なくなったにもかかわらず見られたことも、注目に値すると研究者らが報告している。
http://www.nutritio.net/linkdediet/FMPro?-db=NEWS.fp5&-format=news_detail.htm&-lay=lay&KibanID=29833&-find