今天 NPR 上有一篇文章，介绍 “ 减肥 ” 。（其实， “ 减肥 ” 有点误导读者。） …how about this approach: Simply limit your daily eating window to 10 hours. This means that if you take your first bite of food at 8 a.m., you'd need to consume your last calorie of the day by 6 p.m. 即：每天从上午 8 点开始吃东西，但是，不要在晚上 6 点以后吃东西。也就是说，你有连续 10 小时可以吃、吃、吃。但是，让 你的胃（消化系统）连续“休息” 14 小时。 原文： Eat For 10 Hours. Fast For 14. This Daily Habit Prompts Weight Loss, Study Finds https://www.npr.org/sections/thesalt/2019/12/08/785142534/eat-for-10-hours-fast-for-14-this-daily-habit-prompts-weight-loss-study-finds 里面提到的许多“利”，我深有体会。因为我从 2018 年 6 月开始了“ 9-5 diet ” （每天从上午 9 点开始吃东西，但是，不要在晚上 5 点以后吃东西。）起因是看了下面的一篇文章，感觉有道理。 原文： Early Time-Restricted Feeding Improves Insulin Sensitivity, Blood Pressure, and Oxidative Stress Even without Weight Loss in Men with Prediabetes https://www.cell.com/cell-metabolism/fulltext/S1550-4131(18)30253-5 文章的研究对象是高血压、高血糖患者。为了观察这些人在体重不变的情况下，血压、血糖是否有所改善，可怜的参加者必须在 9-3 之间 吃完三餐！因为最后结果是：血压、血糖“有改善”，文章作者推荐： 可以试一下 9-5 （多两个小时进食时间，没有那么痛苦）。 应该说，每天 5 点之前吃完晚餐 不容易。因为我们不可能没有社交（朋友一起吃饭）。我尽量中午约朋友吃饭。但是，不是严格到 5 点以后一定不吃东西。（各种原因，包括社交，或晚上感觉非常饿时。） 今年 10 月血常规，显示 LDL 正常了。家庭医生问我：你怎么做到的？我当时回答：不知道。后来想到了 9-5 diet 。当然，明年我的 LDL 能否正常，现在不敢说。但是，我觉得可以继续 9-5 diet 。（对于我，改变体重太难了。瑜伽没有、 9-5 diet 也没有大作用。） 现在习惯了晚上不吃东西，偶尔朋友小聚（一周一次？），我会尽量少吃。最怕是晚上聚会有甜食，忍不住，结果就是梦里“比较辛苦”。 如果你想试一下，可以先把晚餐往前移： 7 点， 6 点，最后就能做到 5 点。
一般认为吃素（蔬菜、水果）有益健康，而吃荤（鱼除外） 对健康不利， 尤其是吃红 肉是很多人所忌讳的。美国心脏学会倡导的“膳食防止高血压”（DASH）计划建议人们多吃水果、蔬菜、低脂奶和植物蛋白，以便降低血压和减少心脏病风险。 可是，美国和澳大利亚科学家的最新研究表明，牛肉是理想的蛋白质来源，它也像水果、蔬菜和低脂奶一样可以降低血压。因此，他们提出 用动物蛋白代替植物蛋白的改良DASH计划—— BOLD+ （ Beef in an Optimal Lean Diet plus additional protein ）。 该实验共招募了36位30-65岁的志愿者（收缩压平均为116毫米汞柱），所准备的4种 食物 添加了不同份量的牛肉：1. 美国健康食品（HAD）—— 每天 0.7盎司（20克）牛肉；DASH——每天1.0盎司（28克）牛肉；BOLD——每天4.0盎司（113克）牛肉；BOLD+——每天5.4盎司（153克）牛肉。实验 为期5周，在实验前后分别测定血压。 结果表明，BOLD+组的 血压（ 111.4毫米汞柱） 比HAD组的 血压（ 115.7毫米汞柱） 更低，而DASH与BOLD无显著差异。这表明血压降低取决于总蛋白质 的 摄取，而不是蛋白质的种类（动物或植物来源）。 Eating lean beef daily can help lower blood pressure, study suggests Date: July 17, 2014 Source: Penn State Summary: Contrary to conventional wisdom, new research suggests that eating lean beef can reduce risk factors for heart disease. The DASH eating plan -- Dietary Approaches to Stop Hypertension -- is currently recommended by the American Heart Association to lower blood pressure and reduce risk of heart disease. People following the DASH diet are encouraged to eat fruits, vegetables, low-fat dairy and protein predominantly from plant sources. Lean beef can be enjoyed as the predominant protein source in a DASH-like diet, along with fruits, vegetables and low-fat dairy, to effectively help lower blood pressure in healthy individuals, new research suggests. Contrary to conventional wisdom, a growing body of evidence shows that eating lean beef can reduce risk factors for heart disease, according to recent research by nutritional scientists. This research adds to the significant evidence, including work previously done in our lab, that supports lean beef's role in a heart-healthy diet, said Penny M. Kris-Etherton, Distinguished Professor of Nutrition, Penn State. This study shows that nutrient-rich lean beef can be included as part of a heart-healthy diet that reduces blood pressure, which can help lower the risk for cardiovascular disease. The DASH eating plan -- Dietary Approaches to Stop Hypertension -- is currently recommended by the American Heart Association to lower blood pressure and reduce risk of heart disease. People following the DASH diet are encouraged to eat fruits, vegetables, low-fat dairy and protein predominantly from plant sources. The Beef Checkoff Program and the National Institutes of Health-supported Penn State General Clinical Research Center funded this research. Lean beef can be enjoyed as the predominant protein source in a DASH-like diet, along with fruits, vegetables and low-fat dairy, to effectively help lower blood pressure in healthy individuals, the researchers report in the Journal of Human Hypertension . This DASH-like diet is also called the BOLD+ diet -- Beef in an Optimal Lean Diet plus additional protein. Kris-Etherton and colleagues tested four diets to find the effects on vascular health. The diets tested included the Healthy American Diet -- which served as the control -- the BOLD+ diet, the BOLD diet and the DASH diet. The control diet consisted of 0.7 ounces of lean beef per day, while the DASH diet included 1.0 ounce. The BOLD diet had 4.0 ounces and the BOLD+ diet included 5.4 ounces of lean beef. The researchers tested the four different diets with 36 participants, between the ages of 30 and 65. All participants followed each diet at different times throughout the study period. Subjects were randomly assigned an order to follow each of the four diet plans for five weeks each, with a break of one week in between each new plan. Blood pressure was taken at the beginning and end of each diet period. The BOLD+ diet was more effective at reducing blood pressure when compared to the other diets tested. This evidence suggests that it is the total protein intake -- not the type of protein -- that is instrumental in reducing blood pressure, as part of a DASH-like dietary pattern, the researchers stated. Working with Kris-Etherton were Michael A. Roussell, nutrition consultant; Sheila G. West, associate professor of biobehavioral health; Jan S. Ulbrecht, professor of biobehavioral health; John P. Vanden Heuvel, professor of veterinary science, all at Penn State; Alison M. Hill, lecturer in nutrition, University of South Australia; Trent L. Gaugler, visiting assistant professor of statistics, Carnegie Mellon University; and Peter J. Gillies, professor and director of the Institute for Food, Nutrition and Health at Rutgers, The State University of New Jersey. Story Source: The above story is based on materials provided by Penn State . The original article was written by Victoria M. Indivero. Note: Materials may be edited for content and length. Journal Reference : M A Roussell, A M Hill, T L Gaugler, S G West, J S Ulbrecht, J P Vanden Heuvel, P J Gillies, P M Kris-Etherton. Effects of a DASH-like diet containing lean beef on vascular health . Journal of Human Hypertension , 2014; DOI: 10.1038/jhh.2014.34
在我知道西瓜对健康的这一好处之前，我就喜欢吃西瓜。在整个夏季，我几乎每天都要吃西瓜，而且特别喜欢吃冰冻西瓜（不提倡！）。 我生活在广东，广东人认为西瓜属于“寒湿”的食品， 特别忌讳。我也在他们的影响下减少了食用量，但那样可能会降低西瓜的健康效应。 最近，美国科学家在《美国高血压杂志》（American J Hypertension）发表文章指出，西瓜可以明显降低 超重者在静息时和胁迫下的血压。 早就发现，心脏病往往多发于寒冷的冬天，因为低温使血压升高，心脏不得不超负荷运转，以便将血液泵入动脉血管，这样就会导致流入心脏的血液减少。 肥胖及高血压人士在冬季或低温房间长时间滞留， 突发中风或心力衰竭的 风险极高，而多吃西瓜就能极大地降低心脏病的风险，只是冬天吃西瓜有点难！ 西瓜中富含瓜氨酸，而 瓜氨酸 可以转变成精氨酸 ，精氨酸又能在血管内皮细胞一氧化氮合酶催化下转变成一氧化氮，而一氧化氮正是血管扩张剂。 因此， 若冬天买不到西瓜，就 可以口服含有瓜氨酸的保健品（好像市售的都是精氨酸与瓜氨酸的混合物）。 该实验观察为期12周，在13名患高血压病的肥胖中年男女（女性10人，平均年龄57岁，收缩压约151毫米汞柱）中进行。为了模拟冬季气候， 让参试者将一只手浸入 华氏39度（摄氏4度 ）的水中，然后进行 血压测量及其他测试 。 实验分两期进行，每期6周。将参试者分成两组，一组参试者每天服用2克瓜氨酸制品，另一组则服用安慰剂。在整个实验过程中，停止服用降压药，也不减肥和锻炼。 结果表明，瓜氨酸可使处于低温环境中的参试者血压下降约10毫米汞柱，心率下降约7.3%（以75次/分钟为标准）。从绝对值来看，血压降低的幅度并不大，但对于高血压病人而言，冬季或低温导致心脏病的原因也许就是血压的轻微上升而达到阈值。 另外，也有研究表明，西瓜汁对于缓解运动后肌肉酸痛很有益处，因此运动员或体力劳动者应该多喝西瓜汁或多吃西瓜。 New research suggests that watermelon can be an effective natural weapon against prehypertension, a precursor to cardiovascular disease. Credit: iStockphoto/Serhiy Shullye Chowing down on watermelon could lower blood pressure, study suggests Date: April 3, 2014 Source: Florida State University Summary: Watermelon could significantly reduce blood pressure in overweight individuals both at rest and while under stress. The pressure on the aorta and on the heart decreased after consuming watermelon extract, the small study concludes. Be sure to pick up a watermelon -- or two -- at your local grocery store. It could save your life. A new study by Florida State University Associate Professor Arturo Figueroa, published in the American Journal of Hypertension , found that watermelon could significantly reduce blood pressure in overweight individuals both at rest and while under stress. The pressure on the aorta and on the heart decreased after consuming watermelon extract, Figueroa said. The study started with a simple concept. More people die of heart attacks in cold weather because the stress of the cold temperatures causes blood pressure to increase and the heart has to work harder to pump blood into the aorta. That often leads to less blood flow to the heart. Thus, people with obesity and high blood pressure face a higher risk for stroke or heart attack when exposed to the cold either during the winter or in rooms with low temperatures. So, what might help their hearts? It turned out that watermelon may be part of the answer. Figueroa's 12-week study focused on 13 middle-aged, obese men and women who also suffered from high blood pressure. To simulate cold weather conditions, one hand of the subject was dipped into 39 degree water (or 4 degrees Celsius) while Figueroa's team took their blood pressure and other vital measurements. Meanwhile, the group was divided into two. For the first six weeks, one group was given four grams of the amino acid L-citrulline and two grams of L-arginine per day, both from watermelon extract. The other group was given a placebo for 6 weeks. Then, they switched for the second six weeks. Participants also had to refrain from taking any medication for blood pressure or making any significant changes in their lifestyle, particularly related to diet and exercise, during the study. The results showed that consuming watermelon had a positive impact on aortic blood pressure and other vascular parameters. Notably, study participants showed improvements in blood pressure and cardiac stress while both at rest and while they were exposed to the cold water. That means less overload to the heart, so the heart is going to work easily during a stressful situation such as cold exposure, Figueroa said. Figueroa has conducted multiple studies on the benefits of watermelon. In the past, he examined how it impacts post-menopausal women's arterial function and the blood pressure readings of adults with pre-hypertension. In addition to being published in the American Journal of Hypertension , the study was also published in the US National Library of Medicine National Institutes of Health and was one of the top new hypertensive articles in MDLinx. Story Source: The above story is based on materials provided by Florida State University . Note: Materials may be edited for content and length. Journal Reference : A. Figueroa, A. Wong, R. Kalfon. Effects of Watermelon Supplementation on Aortic Hemodynamic Responses to the Cold Pressor Test in Obese Hypertensive Adults . American Journal of Hypertension , 2014; DOI: 10.1093/ajh/hpt295 你若成风（许嵩） 晚秋（毛宁）
前几天，科学网援引中国新闻网的一则报道： 研究称常用漱口水有风险 ！其出处是《自由基生物学与医学》（Free Radical Biology and Medicine）杂志上发表的一篇最新论文“口腔硝酸盐还原细菌在血压控制中的生理作用“（ Physiological role for nitrate-reducing oral bacteria in blood pressure control ）。这篇文章是open access，点击上述论文的英文标题，即可阅读全文并下载保存。 这篇文章的核心内容是强调”漱口水升高血压“，以前科学网也曾引用过另一篇报道称： 漱口水可能增加口腔癌风险 ！看来漱口水”十恶不赦“，堪称日常生活中危及人类健康的”毒品“。可是，为什么漱口水仍在生产，产品仍在销售（如高露洁的”贝齿“）？当你看到这些报道后，你还会购买和使用漱口水吗？对此，我觉得有必要科普一下，澄清一些模糊认识，也避免一些误会。 为什么漱口水可以让人的血压升高呢？其实原理很简单，一氧化氮（NO）可以通血管，而使用漱口水能减少NO的产生。口腔内含有丰富的硝酸盐（NO 3 - ），它既可直接来自食物，也能由唾液腺分泌，后者来自血液中NO的氧化。细菌含有硝酸还原酶，可以将硝酸盐还原成亚硝酸盐（ NO 2 - ），后者可被人体的酶类（黄素氧化酶、呼吸链酶类、去氧血红蛋白或肌红蛋白等）继续还原成NO。 不难理解，漱口水就是”杀菌水“，其中含有的杀菌成分（如西吡氯铵、氟化钠等）可以使口腔细菌全部被杀死，于是硝酸盐就无法经亚硝酸盐产生NO了。推而广之，按此结果，今后凡是含有杀菌成分的牙膏（如含氟牙膏）都不能购买和使用了，因为要保护口腔细菌，避免血压升高。 有人会问：使用含氟的漱口水或含氟牙膏的后果真的有那么严重吗？根据论文的实验结果，在7天内使用含氯己定（另一种杀菌成分）漱口水的自愿者，其血压仅仅升高了2-3.5毫米汞柱，可能还不及一次面试可能导致的血压升高，何况人体内产生NO的主要途径是由精氨酸在一氧化氮合酶（NOS）催化下合成，而细菌转化的NO含量微乎其微！大家看完下面这张示意图就会完全明白。 这篇文章只是说明一个事实，而并不表明其生理意义有多么重要。必须指出的是，这个实验是用健康志愿者做的，假如你患有口腔疾病（如蛀齿、牙周炎、牙龈炎），除了积极治疗以外，常用漱口水至少可以缓解牙疼，并防止病情恶化。因此，口腔细菌中有害菌对人体的坏处远远大于有益菌对健康的好处。 另外，至于漱口水致癌是基于其含有不纯的酒精成分，其中的乙醛可以致癌。人体对乙醛的耐受性存在个体差异（遗传差异），也就是有人能分解乙醛，有人不能分解。喝一次白酒接触的乙醛比用一次漱口水接触的乙醛要多得多。不过，现在出品的漱口水都不含酒精，所以其致癌风险也就不存在了。 以下是该论文的英文摘要： Physiological role for nitrate-reducing oral bacteria in blood pressure control Circulating nitrate (NO 3 − ), derived from dietary sources or endogenous nitric oxide production, is extracted from blood by the salivary glands, accumulates in saliva, and is then reduced to nitrite (NO 2 − ) by the oral microflora. This process has historically been viewed as harmful, because nitrite can promote formation of potentially carcinogenic N -nitrosamines. More recent research, however, suggests that nitrite can also serve as a precursor for systemic generation of vasodilatory nitric oxide, and exogenous administration of nitrate reduces blood pressure in humans. However, whether oral nitrate-reducing bacteria participate in “setting” blood pressure is unknown. We investigated whether suppression of the oral microflora affects systemic nitrite levels and hence blood pressure in healthy individuals. We measured blood pressure (clinic, home, and 24-h ambulatory) in 19 healthy volunteers during an initial 7-day control period followed by a 7-day treatment period with a chlorhexidine-based antiseptic mouthwash. Oral nitrate-reducing capacity and nitrite levels were measured after each study period. Antiseptic mouthwash treatment reduced oral nitrite production by 90% ( p 0.001) and plasma nitrite levels by 25% ( p = 0.001) compared to the control period. Systolic and diastolic blood pressure increased by 2–3 .5 mm Hg, increases correlated to a decrease in circulating nitrite concentrations ( r 2 = 0.56, p = 0.002). The blood pressure effect appeared within 1 day of disruption of the oral microflora and was sustained during the 7-day mouthwash intervention. These results suggest that the recycling of endogenous nitrate by oral bacteria plays an important role in determination of plasma nitrite levels and thereby in the physiological control of blood pressure.
如果拿一根弹性橡胶管, 让水自由流过. 我们增大进口压, 那么胶管直径会因弹性增加, 从而流量增加. 如果我们拿一根血管,让血自由流过, 我们增大进口压, 那么流量会不会增加? 答案似乎显而易见，那是当然的了。可是，事实上，如果血压变化控制在一定的范围，血管会在初期的膨胀后启动自调节机制而使流量恢复到原先的水准。事实上，在这个过程中，血管直径甚至会有一定程度的降低！ 这个令人惊讶的机制，是英国人William Bayliss于1902年发现的，所以叫Bayliss myogenic response. 其作用机制到底是什么呢？ 原来，血管的伸展使得血管肌细胞去极化(depolarization), 从而使得L-型 通道打开的机率增加而使细胞液里的钙离子增加，从而激发了收缩机制使血管收缩。 这个机制被如下的动物实验验证：使用阻断L-型 通道的药物nimodipine， 结果这个调节机制就消失！见下图： 更长期的myogenic response则是由20-HETE来维持。其机制是减少血管肌细胞 通道的打开几率来维持细胞极性。这一系列漂亮的动物实验是由McCarron等人在小鼠脑动脉上做的【1】。 1. J G McCarron, C A Crichton, P D Langton, A MacKenzie and G L Smith, Myogenic contraction by modulation of voltage-dependent calcium currents in isolated rat cerebral arteries. Journal of Physiology (1997)
最新研究报道 http://news.xinhuanet.com/english2010/health/2010-03/31/c_13231861.htm BEIJING, March 31 (Xinhuanet) -- German researchers recently found having a moderate amount of chocolate may be good for blood-pressure control and therefore better protect the heart, according to a report published on European Heart Journal. Researchers in German Institute of Human Nutrition conducted a study on more than 19,300 people. Over a decade's study, they discovered that those who ate the most amount of chocolate, that is, an average of 7.5 grams a day, had lower blood pressure and a 39 percent lower risk of having a heart attack or stroke compared to those who had an average of 1.7 grams a day, the least among the subjects. http://www.gopubmed.org/web/gopubmed/4?WEB01644h5xtag2beI7I5I00f01000j10040001rl Chocolate and heartand blood pressure 129 documents semantically analyzed 1 2 Top Years Publications 2006 16 2008 13 2009 12 2000 11 2007 10 2001 7 2004 5 1999 5 2010 4 1997 4 1989 4 2003 3 1996 3 2005 2 2002 2 1994 2 1993 2 1991 2 1988 2 1983 2 1 2 1 2 Top Countries Publications USA 34 Germany 6 United Kingdom 6 Japan 5 Australia 5 Italy 4 Switzerland 4 Sweden 3 Spain 3 Canada 3 China 3 Brazil 2 Ireland 2 Turkey 2 Greece 2 Netherlands 2 Taiwan 2 Iran 1 Denmark 1 Nigeria 1 1 2 1 2 3 4 Top Cities Publications Davis 6 Boston 4 Leipzig 2 Stockholm 2 Dublin 2 Milan 2 Zrich 2 London 2 Athens 2 Washington 2 San Francisco 2 Rochester, MN, USA 2 Seattle 2 Porto Alegre 1 Barcelona 1 Afyonkarahisar 1 Newcastle upon Tyne 1 Messina 1 Tokyo 1 Wollongong 1 1 2 3 4 1 2 3 4 5 Top Journals Publications J Clin Microbiol 11 Am J Clin Nutr 8 Am J Hypertens 3 Int J Cardiol 3 Mol Nutr Food Res 3 Am J Cardiol 3 J Cardiovasc Pharm 3 Eur J Clin Nutr 2 Circulation 2 Heart 2 Crit Care Nurse 2 Cardiovasc Res 2 Nutr Rev 2 J Am Diet Assoc 2 J Med Microbiol 2 West Afr J Med 2 J Nutr Biochem 2 Zentralbl Bakteriol Mikrobiol Hyg 2 Expert Rev Cardiovasc Ther 1 Nutr Res Rev 1 1 2 3 4 5 1 2 3 ... 26 Top Authors Publications Keen C 4 Corti R 3 Roberts G 3 Grivetti L 2 Hermann F 2 Sudano I 2 Spieker L 2 Hermann M 2 Lscher T 2 Ruschitzka F 2 Nll G 2 Stefanadis C 2 Vlachopoulos C 2 Alexopoulos N 2 Aznaouridis K 2 Schmitz H 2 Dyerberg J 2 Stender S 2 Cockerill F 2 Vetter E 2 1 2 3 ... 26 1 2 3 ... 66 Top Terms Publications Cacao 121 Humans 102 Adult 40 Heart Diseases 37 Patients 33 Coronary Disease 26 Flavonoids 26 Middle Aged 26 Animals 23 Evaluation Studies as Topic 22 Blood Pressure 21 Culture Media 21 Pressure 20 Eating 20 Cardiovascular Diseases 20 Aged 20 Beverages 19 Incubators 19 Arteries 17 Oxides 17 1 2 3 ... 66
标签: 血压
