2 posts tagged “food science”

Keto + other diet trends: Healthy or hype?

Posted 10 months ago by

Keto. Carnivore. Fasting. What should you know about these diet buzzwords and the potential benefits or risks, especially when you’re living with an existing or chronic health condition? Take a peek (and always talk with your doctor before making big dietary changes).

3 hot diet trends in 2019

According to Google Trends data (accessed in early 2019), some of the hottest topics people are searching for related to “diets” include:

  • Ketogenic diet
  • Carnivore diet
  • Intermittent fasting

What is the “keto” diet?

The ketogenic or “keto” diet is a very low-carb, high-fat diet that’s been around for decades and gained popularity thanks to books, blogs and celebrities/influencers touting it the past two years. Researchers developed the ketogenic diet in the 1920s as a treatment for epilepsy, and some people with epilepsy that doesn’t respond to medication still use the diet to help prevent seizures today.

Most people following the keto diet these days are using it for weight loss. By severely cutting carbs, the body enters ketosis — a metabolic state that burns fat for energy, essentially like starvation mode. The jury is still out on whether ketosis and the keto diet are safe, especially in the long term, because research is lacking.

And when it comes to weight loss, the keto diet doesn’t have a big edge over low-fat diets. “Ketogenic diets can help patients lose about 2 kg [4.4 pounds] more than low-fat diets do at 1 year, but higher-quality studies show no difference,” according to a Canadian Family Physician report published in December 2018. “Weight loss peaks at about 5 months but is often not sustained.”

Critics of the keto diet say it is a fad (like Atkins 2.0) and so extreme that it’s hard to stick with (thanks to the 80% fat, 15% protein, 5% carbohydrate breakdown). Just a slice or two of bread = all your carbs for the day.

But some researchers have been exploring the potential benefits of a ketogenic diet for people with some health conditions beyond epilepsy (such as type 2 diabetes, cancer and other conditions). And there’s a steady drip of studies on “going keto.” However, the studies are fairly limited in size and scope, ketosis is complicated, and nutrition experts say it can cause nutritional deficiencies and possible damage to the kidneys, liver, heart and muscles.

carnivore diet foods, meat and fish

What is the carnivore diet?

In a word: meat. Well, technically there’s no official definition, but this diet trend involves eating “only foods that either walked, swam or flew,” Everyday Health says. In addition to meat and eggs, some carnivore dieters also eat other animal products like milk, yogurt and cheese.

Why are some people rushing to the meat-heavy diet? Many people are using it for weight loss (especially if they’ve tried the keto diet but prefer eating more protein than fat). But some people have also turned to it to try to address inflammation, autoimmune conditions or food sensitivities.

“It’s important to note that this diet is so new that there’s no research on the health effects of an all-meat diet, if a carnivore diet can actually reduce symptoms of autoimmune conditions, or if it is a reliable method for uncovering food intolerances or aiding weight loss,” Everyday Health reports.

Besides being new and unproven, the nearly all-meat diet is controversial for a couple of reasons.

First off, the carnivore diet is even more restrictive than the ketogenic diet and carries some related risks. It calls for not eating any carbs (grains, legumes, bread), fruits or vegetables. Eliminating fruits, veggies and healthy carbs (all part of a healthy diet recommended by the World Health Organization) means people are missing out in important nutrients like fiber, antioxidants and a variety of vitamins. Eating too much protein can strain the kidneys, and a diet high in red and processed meats may increase the risk of stomach cancer, according to 2015 research published in The Lancet.

Secondly, one of the main proponents of the diet, Shawn Baker, who authored the 2018 book The Carnivore Diet, is a former physician whose medical license was revoked in 2017 “based on failure to report adverse action taken by a healthcare entity and incompetence to practice as a licensee.”

intermittent fasting diet, clock on plate

What is intermittent fasting?

Intermittent fasting is another topic covered in dozens of books and on countless blogs these days. This diet is less about what you eat and more about when you eat, and there are several variations and names, including the 5:2 diet, the 16/8 diet, “The 8 Hour Diet,” “The Fast Diet,” the “Warrior Diet,” “The Dubrow Diet,” and the “Eat Stop Eat” method.

These diets call for periods of fasting (or severely limiting your food intake), such as fasting two days in a row each week or only consuming food in an 8-hour window each day. See examples, like the 5:2 diet and 16/8 diet, explained here.

Somewhat similar to the keto diet, the aim of intermittent fasting is to send the body into a metabolic state that burns fat — but the “intermittent” part means this is balanced with periods of normal (ideally, healthy) food intake so that the body doesn’t enter extended “starvation mode.”

A 2013 article in the Canadian Medical Association Journal reported: “There is indeed a large body of research to support the health benefits of fasting, though most of it has been conducted on animals, not humans. Still, the results have been promising. Fasting has been shown to improve biomarkers of disease, reduce oxidative stress and preserve learning and memory functioning, according to Mark Mattson, senior investigator for the National Institute on Aging, part of the U.S. National Institutes of Health.”

A few of the human studies on intermittent fasting (IF) and alternate day fasting (ADF) have focused on overweight adults with asthma and people at risk for type 2 diabetes, with somewhat promising results but calls for additional research.

In general, paying attention to when we eat (over a shorter span of time each day) — but ideally not skipping breakfast or binge-eating on non-fasting days — could have some health benefits for some people, yet more large-scale and longterm studies are needed.

Bottom line? Talk with your doctor and/or a registered dietitian who knows about your health condition(s) and treatments and can help you come up with a healthy eating plan that you’re most likely to stick with. Even if they’re not getting as much attention as the latest diet trends, some less restrictive and more balanced eating plans are still highly regarded (for example, the Mediterranean diet tops the list of U.S. News & World Report’s Best Diets Overall in 2019).

How has your diet or way of eating affected your condition (pro or con)? Join PatientsLikeMe or log in to connect with others on this topic in our forum. Also, complete your PatientsLikeMe profile with the latest treatments or lifestyle adjustments you’ve tried and how they’re working for you. For example, you can add diet types (such as Mediterranean or low-carb/high-protein) to your profile (once you’re logged in, click the “My Health” tab). Together, we can learn more.


Why is dietary advice so all over the place? Nutrition experts explain

Posted September 18th, 2018 by

If you’re confused about what kind of milk to drink, what type of cooking oil is “healthiest” or whether the Mediterranean diet is the ticket to heart health, you’re not alone. Nutrition experts dig into the complexity of dietary research.

Digesting dietary advice

The constant churn of nutrition news, books and blog posts — combined with the growing number of food options at the grocery store — can feel contradictory and make your head spin when it comes to making healthy diet decisions.

“As a dietitian, even I get tripped up when new studies that come out that question my beliefs,” Washington Post writer Cara Rosenbloom admits in a recent article on “how to handle ever-changing nutrition science.” She interviewed Dariush Mozzafarian, the cardiologist and researcher behind this 2018 BMJ analysis of nutrition science.

They make the case that we have an issue with how we “digest” food advice:

  • We take it very personally. “If you learn in physics that there was new research about a black hole, you may say, ‘Oh, that’s interesting,’ but you don’t change your habits because the science has changed,” Mozaffarian says. But people these days tend to swiftly avoid or adopt foods (such as wheat/gluten or coconut oil) based on new information or faddish magazine reports that may not warrant dietary changes.
  • We cling to every new study. New nutrition research comes out weekly but people (and policymakers) would be wise not to focus on single studies, Mozaffarian argues. Understanding the relationship between foods, wellness and disease takes a long time.
  • We don’t have centralized government guidelines. The U.S. Department of Agriculture (USDA), the Food and Drug Administration (FDA) and the Department of Health and Human Services (HHS) are just a few sources of government recommendations on nutrition. Mozaffarian says a cabinet-level position that centralizes or coordinates nutrition guidelines would help eliminate confusion.

Other issues + pointers

Other nutritionists point out that dietary science is still in its infancy (see this infographic), and most nutrition studies are observational (rather than randomized control trials, which offer more evidence about “X may cause Y or Z”).

Researchers behind a major study on the Mediterranean diet and heart health recently had to retract and re-analyze their work because it was flawed (although version 2.0 reached the same conclusion — the Mediterranean diet can be beneficial for those with cardiac risks).

Even if you’ve figured out your own eating plan or nutrition philosophy (like Michael Pollan’s famous one: “Eat food. Not too much. Mostly plants.”), articles about diet still make great clickbait. Look for pieces that ask questions and cite research and credentialed nutrition experts, rather than making blind declarations or heavily promoting certain products. And always check with your own doctor or care team before making dietary changes or even taking new vitamins or supplements.

Do you follow a certain eating plan or style? What do you struggle with most when it comes to eating (or understanding nutrition advice)? Join PatientsLikeMe or log in to connect with the community in this forum discussion. As a member, you can also add any supplements or diet types (such as Mediterranean or low-carb/high-protein) to your profile (under the “My Health” tab) to assess them and track a more complete picture of your health.

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