The Keto Diet: A Beginner’s Guide

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Written By: Zan Strumfeld

To keto or not to keto, that is the question.

If you’ve turned on your phone or talked to most humans lately, you’ve probably heard someone talking about the keto diet. It’s a food craze sweeping the nation. Halle Berry and Tim Tebow are eating it up. It’s likely your friend, coworker or mailman is following the plan as you read this. Considering it yourself? Here’s a quick rundown of what you’ll been getting into.

Let’s start with the basics. What is the keto diet?

The ketogenic diet—keto diet, for short—calls for a drastic reduction of carbohydrates and a high intake of fat. This means eliminating any high-carb/high-sugar foods from your diet: no sources of refined sugars, processed grains, whole grains, starchy vegetables and even most fruits. Instead, you’ll take in fat…and not much else.

Wait, you can eat fat and lose weight? Yep. Research claims high fat intake actually extends your life. Though keep in mind, these are unsaturated fats, like salmon, extra virgin olive oil, and avocado, which are filled with omega-3s (fatty acids) that provide brain fuel and glowing skin. More on what you can eat later.

For starters: know your macronutrients, aka macros. The three main macros are carbs, protein and fats. When you’re eating, you’ll need to make sure your daily carb intake is under 30 grams total a day, and eat 0.8 times your lean body mass in protein. So, if you’re a 145-pound, 5’6’’ woman, your lean body weight is roughly 105 pounds. That means you’ll want to aim for 84 grams of protein and about 100 grams of fat on a daily basis.

How do you lose weight on the keto diet?

Once your body begins adjusting to the diet, you’ll fall into what’s called “ketosis,” or a natural metabolic state. It’s pretty easy to get here by restricting your carbohydrates and protein, not worrying about fat intake, avoiding snacks, drinking lots of water and—like any diet—exercising. Your body will begin solely burning fat and making ketones, a natural acid that moves to the bloodstream. Here’s where your body starts maximizing weight loss and supplies a high amount of energy for the brain.

But how will you know you’ve fallen into ketosis? Well, it’s important to measure your ketone levels to make sure you’re hitting optimal levels to reach your weight loss goals. You can track this in a number of ways right at home. There are plenty of pricey urine and blood strips you can use, or you can simply listen to your body’s symptoms. You’re on the right track if you have the good—a clearer and higher-functioning mental state, reduced cravings for food and increased energy—and the bad—increase thirst, increased urination, dry mouth and maybe a bit of bad breath.

All in all, you’ll lower your blood sugar and insulin levels dramatically. And, of course, lose weight.

How will I benefit from the keto diet?

There are a quite a few positive outcomes from being keto. First and foremost: weight loss. When your insulin levels drop, your body becomes a fat-burning beast. This directly helps you control your blood sugar levels based on the foods you’ll eat. Since you’re burning fat like crazy, your energy will greatly increase. Your brain will even function at a higher level. Plus, fats help you feel satisfied for longer periods of time, and cut your cravings for sugary, high-carb foods. Certain studies have shown improvement in high blood pressure and cholesterol. One study even claims it helps reduce acne. And while there’s still plenty of research to be done, the keto diet has been said to benefit those with diabetes, Alzheimer’s, high blood pressure, fatty liver disease and much more.

Also keep in mind there are a few different types of keto diets (anywhere from basic to bodybuilder), based on your desired results.

So, what can I eat?

Here’s the simplest breakdown (or a longer list):

• Meats: grass-fed and organic, including beef, line-cut fish, lamb, poultry, eggs  

• Veggies: above ground, including mushrooms, Brussels sprouts, broccoli

• Greens: non-starchy, including spinach, lettuce, kale

• Dairy: high fat, including butter, soft cheese, heavy cream

• Nuts and Seeds: walnuts, macadamia, sunflower

• Berries and Avocado: low-glycemic, including raspberries, blackberries

• Oils: coconut, MCT, extra virgin olive oil

What should I avoid eating?

This one’s easy: sugar. Unfortunately there are lots of (sometimes sneaky) names for it. Stay away from syrups (including corn, brown rice, high fructose), things that seem cryptic (diastatic malt, scant, dehydrated cane juice) and words that read like a chemical (dextrose, maltodextrin, saccharose). High sugars are also found in natural foods, including molasses, honey, agave and dried fruit.

Avoid any refined starches including wheat (flour, orzo, bran), corn, grains (rice, quinoa, oats) and starchy vegetables (sweet potato, potato), soy, most beans and legumes.

Let go of processed vegetable oils (including canola, corn and soybean) and (always) keep away from trans fats. Lastly, you won’t be able to replace your sugar with any alternatives or artificial/natural sweeteners (that includes Stevia!).


What about the side effects? Is the keto diet safe?

Besides the frequent peeing and dry mouth, there’s one more thing you’ll want to know about. They call it the “keto flu,” and it’s pretty much what it sounds like: sleepy, headachey, irritability, foggy brain-y. You may crave sugar like crazy, be constipated, have trouble sleeping and lack of motivation to exercise. Most people experience these symptoms during the first week or two of the diet.

Fortunately, it’s short-lived, and it’s your body’s way of transitioning from burning sugar to burning fat, or kicking into ketosis—the primary goal of the diet. You can alleviate some of the keto flu effects by taking it easy with physical activity (no complaints there) and increasing your water intake. Remember, this is all a normal part of the process. That bad breath I brought up earlier? It’ll be at its peak stink during the keto flu.

And, while we’re at it, there are few other things to watch out for. Increased diarrhea’s a real, which can be from a lack of fiber in the diet. It’s also possible to reach too much ketone production, where the body falls into a dangerous condition called ketoacidosis; this is extremely rare, unless you have type 1 diabetes (check with your doctor if you are, since this can be fatal).

Is it safe? Well, it often depends on who’s answering. There are plenty of benefits to a low-carb diet: appetite reduction, immediate weight loss, increased levels of good cholesterol, and much more. While it’s safe to do short-term, many doctors stress that the keto diet removes key nutritional components needed for a healthy diet and lifestyle. By drastically cutting carbohydrates, you’ll miss out on the natural benefits of some foods, including fruit, starchy veggies, whole grains and legumes. And, as of now, there haven’t been enough long-term studies to really show the diet’s lasting effects on the body.

One thing we do know: it reduces seizures. The keto diet actually began in the 1920s for the treatment of epilepsy. It was mostly prescribed for children, with not enough backing research to prove beneficial for adults. So, it’s been around a long time.

Keto and Cancer: Fighting Combo?

For cancer patients, nutrition is key. Cancer treatments like surgery, chemotherapy and radiation can be harsh on the body, so keeping a healthy and stable diet is crucial. (Check out these five vegetables to lower your cancer risks.)

Currently, most of us are under the impression that sugar can cause cancer, or helps fuel cancer cells. Even though research does show that obesity increases the risk of certain types of cancer, including ovarian and pancreatic, there still isn’t strong evidence that following a sugar-free diet lowers cancer risks or boosts survival rates. In fact, all cells, including cancerous ones, use glucose as their primary source of fuel. Healthy cells need sugar, and there’s no way to provide glucose for them and not the cancer cells. And, some research claims that an ultra-low-carb diet could actually damage long-term health by removing good sources of fiber and vitamins from the diet. Many keto-safe foods, like high intakes of red meat, can actually increase your cancer risk.

With all that said, a number of studies have found a link between the keto diet and slowed growth of tumors in mice. One specific study found that, compared to a standard diet, the keto diet increased survival in mice by 56%, bumping up to 78% when combined with oxygen therapy. In September 2018, researchers at the University of Alabama at Birmingham stated that “women with ovarian or endometrial cancer who followed the ketogenic diet for 12 weeks lost more body fat and had lower insulin levels compared to those who followed the low-fat diet.” The study showed a number of favorable effects in two of the deadliest cancers among women, often linked to obesity and high levels of insulin.

Depending on your type of cancer or treatment, Senior Clinical Dietician at MD Anderson Cancer Center Maria Petzel says, the keto diet can be helpful for some, and harmful for others. As cancer is a case-by-case issue, the body may not be able to break down the high proteins and fats required in the keto diet, leading to digestive issues.

The Takeaway

While the keto diet will help you drop the pounds, it’s important to look at some of its noted controversy—especially on how to keep the weight off. Like any lifestyle-changing diet, you should do a bit of research (check out some books like this) and consult your doctor if you’re at any health risks. If you do take the plunge, keep in mind that keto isn’t often seen as sustainable or good for your long-term health. Plan on making your own long-term commitments by finding a healthy balance for a healthier lifestyle. Remember: know your body, know what you’re capable of handling. Just because it’s trendy, doesn’t mean it’s right for you.