Answers to 15 Burning Questions About the Keto Diet

When it seems like everyone — not just celebrities — is on theketogenic diet, you want to know if it’ll work for you. The so-called keto diet is a high-fat, moderate-protein, very low carb plan. But while people say that you can eat all the butter and bacon you want, is that really true (or healthy, for that matter)? And is the keto饮食actually the best way to lose weight? Can it cause more problems than it solves? Here are your top questions, answered.

1.酮饮食健康吗？

In reality, you don’t have to go on the keto diet in orderto behealthy. The keto diet is a therapeutic diet used to control seizures in people who have癫痫, according to癫痫基金会。For these people, a keto diet may be necessary for their health.

但是今天,饮食已成为时尚,许多体育ople are using it to lose weight. Eating high levels ofsaturated fatmay pose a risk for long-term heart health; and in the short term, severely low carb diets may come with unpleasant side effects, likeconstipation和headaches, notesthe Mayo Clinic。鉴于酮的限制性（它消除了大多数水果和乳制品，全谷物，许多蔬菜和豆类），您也可能缺少某些营养素，例如fiber。

2.酮饮食是否可以安全？

Even though following an extremely high fat diet can feel like a radical way to eat, “the research looking atketosisvia diet has not shown any real negative consequences when done in the short term,” saysScott Keatley, RDN，纽约市的Keatley医疗营养疗法。（酮症是自然的代谢状态，使酮会导致体重减轻。）

But there have been few long-term studies, adds Kendra Whitmire, a nutritionist and dietitian in Laguna Beach, California, who practices functional and therapeutic nutrition. It’s difficult to definitively say that it’s safe, and it also largely depends on the types of foods you’re eating on a keto diet. (For instance, olive oil is a healthier choice than butter; salmon is healthier than bacon.) That said, following the keto diet properly, and particularly with help from a medical professional, should reduce negative health effects, says Whitmire.

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3.酮症不好吗？

Typically, your body breaks down carbohydrates as its preferred fuel source. Ketosis is when your body has switched into a fat-burning state and breaks down fat into ketone bodies that are used as energy. Beyond theketo flu, “many studies have shown that entering ketosis via diet does not have any real negative consequence in the short term,” says Keatley.

But long-term studies are needed to truly assess the impact, he adds. Bottom line: Putting your body into ketosis for a limited time is likely not harmful.

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4. How Many Carbs Do You Actually Eat on a Keto Diet?

纽约州怀特普莱恩斯（White Plains）的私人诊所的注册营养师营养师吉尔·基恩（Jill Keene）表示，酮饮食通常由70％至75％的脂肪，20％到25％的蛋白质和5％至10％的碳水化合物组成。每个人的碳水化合物克（g）的确切数量将有所不同，但通常每天约20至50 g。许多酮饮食中的许多人都计数“净碳水化合物”，这是总碳水化合物减去纤维。纤维没有在carbohydrate总计，因为它没有消化。无论哪种方式，这一数量的碳水化合物都非常低，需要仔细的计划。吃一点水果，starchy vegetables, sugary foods, or whole grains can easily kick you out of ketosis.

5. CanYou Drink Alcohol on the Keto Diet?

Yes. “Even though there are [often] carbs in alcohol, you can still drink it in limited amounts,” says Keatley. Realize that on days when you do choose to consume alcohol, depending on what you choose, you may have to adjust your carbs from other sources. This may mean making tough decisions, like having a drink but skipping a small amount of fruit or Greek yogurt.

In general, the simpler the better: Spirits are the best choice (avoid mixers that have calories), followed by wine. Your best bet is to stick with a half drink, says Keatley. Because of their lower alcohol percentage and other ingredients, beer and wine “can eat up a lot of your carbs, and they don't give back in terms of vitamins and minerals. It’s a waste of your carbs,” he says.

每种酒精饮料都包含在碳水化合物方面：

Spirits: gin, rum, vodka, whiskey, 1.5 fluid ounce (fl oz), 0 g carbs (1 serving)

红葡萄酒, 5 fl oz, 4 g carbs (1 serving)

White wine, 5 fl oz, 4 g carbs (1 serving)

轻啤酒, 12 fl oz, 6 g carbs (Stick to half of a beer if this is your choice.)

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6. How Much Weight Can You Lose on the Keto Diet?

毫无疑问，生酮饮食可能有助于刺激体重减轻，并且很容易找到有关剧烈转化的轶事报道。“我有客户因酮饮食而减轻了很大的体重，但是他们开始时肥胖，而且有很多脂肪要减少。这些人的身体转变相当大。

In一项研究于2017年2月发表在Journal of Clinical Endocrinology, 20 people with obesity who followed a very low calorie keto diet for four months lost an average of 44 pounds (lb), mainly from body and visceral fat. (It’s important to note that there was no placebo group and this was a small sample source, so the findings are limited.) Inanother study published in February 2017, in营养代谢, normal-weight adults who followed a non-energy (calorie) restricted keto diet for six weeks lost about 4 lb in both fat and lean body mass.

但是长期研究表明，酮和其他饮食之间的体重减轻没有太大差异。One meta-analysis published in October 2013 in theBMJ将成年人与传统低脂饮食中的成年人（食用少于50 g碳水化合物）与那些饮食进行了比较。至少一年后，与削减脂肪的群体相比，酮饮食上的那些饮食量增加了两磅。最重要的是，包括酮在内的饮食可能会帮助您长期减轻相同的体重。凯特利说，有了这个消息，知道可能有更好的选择。

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7.我可以吃什么水果the Ketogenic Diet?

水果是生ally not a mainstay of the keto diet. With so much natural sugar, fruit generally has too many carbs to be included. But you can have small amounts of lower-carb fruits, likeberries, says Whitmire. And if you’re really getting technical,牛油果和coconut, two higher-fat foods, are, in fact, fruits. Based on U.S. Department of Agriculture carb counts, here’s what can fit on keto:

覆盆子：每½杯3克净碳水化合物

Strawberries: 2 g net carbs per ¼ cup slices

蓝莓：4 g net carbs per ¼ cup

Blackberries: 3 g net carbs per ½ cup

Coconut: 2.5 g net carbs per ½ cup, shredded, raw (unsweetened)

Avocado: 3 g net carbs per 1 cup, cubes

*All carb values are net carbs, which is total carbs minus fiber. Fiber is often not counted in net carb totals, as the nutrient isn’t digested.

8.我可以在酮上吃诸如爆米花，燕麦片和酸奶之类的小吃吗？

不幸的是，高碳水化合物等爆米花或oatmeal可能不适合酮饮食。One cup of air-popped popcorncontains 5 g of net carbs, which may be ¼ of your carb allotment for the entire day. It’s also worth mentioning that one cup of popcorn is not a large serving; it contains just 30 calories and no fat, so it won’t be filling. Oatmeal likely doesn’t fit, either. About ¼ cup of plain dried oats (about ½ cup cooked) has 12 grams of net carbohydrates for 77 calories and just one gram of fat.

As for yogurt, it depends on what type you choose and whether it’s keto-compliant.About half of a 7 oz container of Fage plain 5 percent milkfat Greek yogurt, for instance, contains 3 g of carbohydrates. Remember to choose plain versions, as flavored will add more sugar (and, therefore, carbs).

Betterketo-compliant snacks包括坚果（1盎司almondsWhitmire说，有3 g净碳水化合物）（½杯葵花籽仁含3克碳水化合物），以及少量的低碳水化合物水果（如浆果）。牛肉干和非凝乳蔬菜，例如broccoli和cucumbers are other good snack options on keto.

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9. Should I Be Concerned About the Keto Flu?

If you’re interested in the keto diet, you have probably read about the keto flu, one not-so-fun side effect. “The keto flu is definitely real,” says Keatley. “Your body functions really well on carbohydrates — that’s what it was designed for. When it switches to fat burning, it becomes less efficient at making energy,” he says. On keto, you have less energy available and you may feel sick and sluggish, kind of as if you have the flu. As your body naturally adjusts to this new way of drawing energy, you will come out of it. This may take a couple of weeks, says Keatley.

10.酮饮食会给我肾结石吗？

的发展肾结石is certainly a concern if you’re switching to a diet in which you’re eating more protein. (Though, again, the keto diet is more of a moderate-protein diet.) “Consuming high levels of red meat and not drinking a lot of water may make stones more likely,” says Whitmire. She adds that on a keto diet, you need to stay hydrated and replenish electrolytes (minerals like sodium,钾, magnesium, and calcium). “If not, this can increase your risk of side effects like stones,” she says. Past research gives a small glimpse into how likely stones may be.发表在Journal of Child Neurologyon children using the keto diet to control epilepsy found that about 1 in 15 developed kidney stones, though supplements of oral potassium citrate reduced this risk. Talk to your doctor if you have risk factors, like a family or personal history of stones, about any precautions you should take when on the keto diet.

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11. How Might the Keto Diet Affect My Period?

您可能会看到月经的变化。“Studieson younger women who eat severely low-carb for an extended period of time end up withirregular periodsor missed periods,” explains Whitmire. Severely limiting carbohydrates may be taxing on the adrenal system, leading to hormonal imbalances that disrupt a woman’s cycle. Similarly, rapid weight loss can also have this effect. The takeaway? “Women may need more carbs on a keto diet compared to men, especially if a woman is noticing a change in her [cycle],” she adds.

在频谱的另一侧，有限的证据表明polycystic ovary syndrome (PCOS), a ketogenic diet may improve their hormonal balance.The small study, published inNutrition & Metabolism, found that a small group of妇女患有PCOS跟随酮饮食的24周，他们的体重减少了12％testosterone和insulin levels. Again, talk to your doctor, especially if you’re using the diet as part of your treatment.

12. How Long Do You Need to Stay on the Keto Diet to Lose Weight?

Keatley说，许多人报告说，酮饮食迅速减肥。Research in theJournal of Clinical Endocrinology发现肥胖的节食者在四个月内平均损失了44磅的摄入量，这是在非常低的卡路里酮饮食中。也就是说，基特利（Keatley）向客户建议，他们在酮症中花费不超过12周nutritional deficiencies。

他说，当人们减少酮饮食并开始将更多的碳水化合物纳入自己的一天时，他们倾向于在此调整期间恢复体重。如果他们返回在计划中被剥夺后，他们还可以恢复失去的所有体重，并可能更多地恢复到酮前的进食方式。

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13.酮饮食将如何影响您的胆固醇水平？

The interesting thing about a keto diet is that it often leads to weight loss, something that by itself can improve blood lipid levels. At the same time, you may be consuming more saturated fat than ever, in the form of butter, bacon, cream, and椰子油。

长期以来，我们一直警告过吃量过多的饱和脂肪可以raise cholesterol，因此使我们有心脏病的风险。因此，许多专家表示，增加脂肪摄入量可能对已经患有心脏病或患有危险因素的人特别有害。

A studyon obese patients on a keto diet found that after 24 weeks, total胆固醇水平下降，而“坏”低密度脂蛋白胆固醇decreased and “good”HDL胆固醇increased. This could be reflective of the fact that any weight loss, no matter how it's achieved, tends tolower cholesterol。另外，正如已经提到的那样，患有心脏病危险因素的人需要在尝试酮饮食之前咨询医生。Research, as in this study in theBritish Journal of Nutritionin April 2013，得出的结论是，在患有心血管疾病风险的患者中，碳水化合物低的饮食含量低，但脂肪和蛋白质受损的动脉功能较高。

可能的是您在酮上消耗的脂肪类型。2013年12月发行的评论和荟萃分析Journal of the Academy of Nutrition and Dieteticslooked at the effect of a low-fat versus a低碳水化合物饮食on blood lipids. While lower intakes of saturated fat were associated with lower cholesterol levels, higher intakes of monounsaturated fat (likeolive oil在高脂饮食的背景下，或鳄梨与心脏保护性HDL胆固醇水平升高有关。

14. How Much Protein Will You Eat on the Keto Diet?

A typical keto diet may include 20 to 25 percent of calories coming from protein, says Keene. One common misconception is that this is a high-protein diet, when in reality, it’s moderate in protein. “Too much protein can be converted and broken down as sugar to be utilized as an energy source,” she says.

也就是说，您不想蛋白质过低。惠特米尔说：“如果减肥，您希望能够留在酮症中而无需牺牲瘦体重（肌肉）。”这可以松散地等于每公斤体重的1.2至1.5 g蛋白质。（建议的每日津贴目前为每公斤体重0.8克Harvard Health Publishing, so under keto it’s significantly more.) Therefore, a 140-lb woman may aim for 76 to 95 g per day. For reference, one 3.5-ounce skinless chicken breast offers 31 g of protein.

One of the bestsources of proteinon a keto diet is fatty fish (like salmon or mackerel), says Keene, as it offers a source of heart-healthy protein and omega-3 fatty acids.Eggs是另一个不错的选择；one large egg contains6 g of protein and 5 g of fat.

虽然酮饮食可能专注于脂肪，但这并不意味着您必须整天吃培根和香肠。有瘦蛋白的空间，例如鸡肉或鳕鱼；她说，只需记住将脂肪（例如，用橄榄油烤鸡肉）到这些较低的脂肪来源中。许多切割的牛肉也被认为是瘦或额外的瘦肉，因为它们含有10 g或更少的总脂肪以及适度的饱和脂肪（分别为4.5或2 g或更少）。其中包括圆形烤和牛排的眼睛，牛loin尖端牛排，顶部圆形烤和牛排，底部圆形烤和牛排以及顶牛lo牛排the Mayo Clinic。

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15.酮饮食可以反向2型糖尿病吗？

“Though this isn’t the first tool I’d use to help someone control their insulin — carb counting, evenly distributing carbs throughout the day, may be easier to commit to — it’s not off the table, especially with stronger emerging research,” says Keene.

的确：一些初步研究表明，对于某些2型糖尿病患者而言，Keto可能是一种很好的方法。例如，one small February 2017 study in theJournal of Medical Internet Researchrandomized overweight adults with type 2 diabetes into two groups: one that consumed a keto diet, and a control group that ate a low-fat diet recommended by the American Diabetes Association. After 32 weeks, the keto group saw theirA1C(a measure of average blood sugar over a three-month span) fall more compared with the control group, and half lowered their A1C to less than 6.5 percent (less than 5.7 percent is considered normal). The keto group also lost 28 lb compared with about 7 lb for the control group.

But long-term studies are needed, and keto can pose health risks to people with diabetes, especially if you’re following it without supervision from a medical professional. Importantly, anyone who is on medication to lower blood sugar or who is using insulin should be aware that drastically cutting carbs, as you must do on keto, can lead to dangerously low blood sugar,researchshows. Unaddressed, this condition, calledhypoglycemia，可能导致癫痫发作，意识的丧失和视力模糊the Mayo Clinic。(People with type 1 diabetesshould not try the keto diet, experts warn.)

The takeaway? Be sure to work with your doctor if you have type 2 diabetes, and manage your expectations. Not only is there no consensus on whether keto is an effective diet approach for diabetes, it’s also tough to stick with, according toresearch published in the欧洲营养杂志2018年3月。Keep in mind that type 2 diabetes cannot be reversed, but it can be put into remission.

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