Drinking more than a tablespoon or so of olive oil in a day can have a laxative effect. That can lead to diarrhea, which leads to dehydration and possible laxative dependency. Also, olive oil does contain calories. Dipping bread in olive oil instead of buttering it will save you the saturated fats in animal products, but a tablespoon of olive oil contains 120 calories, where a tablespoon of butter only has 100. Twenty calories isn’t enough to tip the scales, but calories can add up fast if you’re not paying attention.
So don’t reward olive oil with the laurels, agreed Dr. Alice Lichtenstein, one of the nation’s top nutrition scientists, at the Human Nutrition Research Center on Aging at Tuft University in Boston. In several interviews about this study of Greek adults, she said, “If the main message that Americans get is to just increase their olive or canola oil consumption, that’s unfortunate because they will increase their caloric intake and they are already getting too many calories.
Combine that with the fact that your body is excreting more water, and you have a potential recipe for clogged pipes. You can keep things moving by getting some fiber from keto-friendly foods like avocado, nuts, and limited portions of non-starchy vegetables and berries, says David Nico, PhD, author of Diet Diagnosis. Upping your water intake helps, too.
Day 13: I have a love-hate relationship with this intermittent fasting thing. I think it's "working," and by that I mean I'm losing some weight. (Plus, improved body composition and definition can come with weight loss.) When I ask Dr. Axe if I should attribute my success to keto or IF, he says both. "I would say 80/20 it's more strongly in the favor of keto, but intermittent fasting does help as well," he says. The fat-burning capabilities of keto have more strength behind it when it comes to weight loss, specifically, he adds, but the intermittent fasting can be great for digestion and just feeling good.
Eating extra virgin olive oil as part of a diverse Mediterranean diet is clearly beneficial in Spanish adults. And although genes partially control preferences, there is no reason to believe it won’t work in other cultures and populations. If we start educating people to use high-quality extra virgin olive oil early in life and change its stigma as a medicine or punishment, we could make our populations and our gut microbiomes healthier. Although we are unlikely to ever match the Greeks.
But your heart health might depend on what you actually eat. Research published in the New England Journal of Medicine suggests that low-carb diets based mostly on plant sources of fat and protein (like avocados or nuts) can lower heart disease risk by 30 percent. But those benefits didn’t hold for people who ate mostly animal-based proteins and fats. (Think: bacon, butter, and steak.)
Recently, many people have begun to question the usefulness of BMI as a general indicator. A sizable amount of people who may be overweight or even obese may be classified as such even though they have a high amount of muscle. Conversely, people with a “healthy” or low BMI may have a high level of body fat and actually be at a greater risk for developing health problems. [5, 6]
Then there’s what you won’t eat. Palinski-Wade gives your body a break from the worst waist-plumping culprits. That means you’ll skip sweeteners and processed starch, which set off blood-sugar spikes strongly linked to belly-fat storage. Trans fats and red meat are also out, since both can worsen a type of cellular inflammation and make belly-fat hormones go haywire.
The go-to protein in the Mediterranean diet is fish. In particular, this diet emphasizes fatty fish like salmon, sardines, and mackerel. These fish are rich in heart- and brain-healthy omega-3 fatty acids. Even those fish that are leaner and have less fat (like cod or tilapia) are still worth it, as they provide a good source of protein. If you currently don't get a lot of fish in your diet, an easy point of entry is to designate one day each week as "fish" night. Cooking fish in parchment paper or foil packets is one no-fuss, no-mess way to put dinner on the table. Or try incorporating it in some of your favorite foods, like tacos, stir-frys, and soups.
This content is strictly the opinion of Dr. Josh Axe and is for informational and educational purposes only. It is not intended to provide medical advice or to take the place of medical advice or treatment from a personal physician. All readers/viewers of this content are advised to consult their doctors or qualified health professionals regarding specific health questions. Neither Dr. Axe nor the publisher of this content takes responsibility for possible health consequences of any person or persons reading or following the information in this educational content. All viewers of this content, especially those taking prescription or over-the-counter medications, should consult their physicians before beginning any nutrition, supplement or lifestyle program.
The premise of the ketogenic diet for weight loss is that if you deprive the body of glucose—the main source of energy for all cells in the body, which is obtained by eating carbohydrate foods—an alternative fuel called ketones is produced from stored fat (thus, the term “keto”-genic). The brain demands the most glucose in a steady supply, about 120 grams daily, because it cannot store glucose. During fasting, or when very little carbohydrate is eaten, the body first pulls stored glucose from the liver and temporarily breaks down muscle to release glucose. If this continues for 3-4 days and stored glucose is fully depleted, blood levels of a hormone called insulin decrease, and the body begins to use fat as its primary fuel. The liver produces ketone bodies from fat, which can be used in the absence of glucose. 
“The general body of research says that once you have two or more tablespoons a day, you’ll improve your blood pressure, your glucose levels and your good cholesterol,” Flynn says. “But I’ve found that the weight-loss effect comes into play at three tablespoons, so that’s what I recommend. It’s an amazing food – it does all these things that help your body, plus it tastes good.”