(upbeat music) – Hi, I'm Susan Taylor with Scripps Health in San Diego, California. There's lots of diets out
there to help you lose weight. We're gonna talk about the Keto diet, and the Paleo diet. Joining us is Dr. Samantha Harris. She is an endocrinologist who specializes in weight management at Scripps Clinic in
San Diego, California. Dr. Harris, thanks so
much for being with us. – Thank you for having me, Susan. – So what is the keto diet? – So the keto diet sort of varies in terms of definition, but it's essentially an eating plan low enough in carbohydrates that people start using
fat for fuel and energy as opposed to carbohydrates.
– What is ketosis? – So when people are eating
low enough in carbohydrates, they can enter the state of ketosis. Or even if they're not eating, they can enter the state
of nutritional ketosis. And that is where the body really relies on the breakdown of fat, and the byproducts of
this, which is ketones, for energy as opposed to
using carbohydrates for fuel. – So how do you know that you've entered that state of ketosis? – Well there are a lot of ways to tell. There are mechanisms out there
that can test your breath, that can check your blood, that can even check your urine. But most people are able to tell. A lot of times they might feel thirstier, they might be urinating more frequently, even lose a few pounds pretty quickly in the first few days. It can also cause a change in taste, like a metallic taste in the mouth, or a change in your breath. It can effect your stomach, sometimes causing a little bit of nausea, a decrease in appetite, more energy. Sometimes difficulty sleeping as well, especially in the beginning.
– Talk about intermittent fasting and its effect on ketosis. – Yes, so intermittent fasting comes in a variety of different forms. The most common being
time-restricted eating, where most people will eat
for an eight hour period of time during the day, and then fast for 16 hours, until the next day, and continue that cycle. During periods of fasting, especially while not eating anything, and we're not eating carbohydrates, our body really has to turn
to an alternative fuel source, which is fat.
So it breaks down fat, which can lead to more ketones as a source of fuel and energy since we're not really eating, and don't have that immediate
source of carbohydrates. – What foods can you eat on this diet? – That really can vary
based on which keto plan somebody is following, but essentially animal protein is very low in carbohydrates. Most fat sources are also
low in carbohydrates. So things like beef, chicken, fish, eggs, sources of fat like certain oils, mayonnaise, some cheese, and then vegetables as well. Some plans permit other food such as nuts and fruit, but it really depends how
strict of a low carb plan somebody is following.
– And what foods do you
need to avoid on this diet? – Yeah, so anything that is
really high in carbohydrates. So simple sugars, processed sugars, things like juice,
starches, bread, potatoes, corn, rice, even fruit can
be very high in carbohydrates and sugars, depending on the fruit type, so a lot of people are
limiting those as well. – What kind of fruit would
you limit on this diet? – So usually the fruits
that are higher in sugar include the tropical fruits, so things like pineapple,
grapes, bananas, mangoes, papaya.
And things that are lower in carbohydrates are usually berries such as blueberries, raspberries and strawberries. – How long do you stay on this diet? – Well, the truth is any
time somebody does a diet, it really should be an eating plan that is a permanent solution because any time someone does
a temporary change in eating and eventually goes back to eating the way they were beforehand, they run the risk of regaining the weight that they had lost. So in general I only
recommend people follow any type of eating plan, whether it's keto, paleo or otherwise, if they're really committed to it pretty much forever. – Who's a good candidate for this diet, and who should avoid this diet? – So a good candidate
for a keto eating plan would be somebody who is very motivated, enjoys the food in the plan, and wants to do it forever. Because really it's a longterm solution and not a short term plan. The people I usually
recommend not following it are people who cannot eat protein, for example if they have
advanced kidney problems, women who are pregnant or nursing really should not be in
the state of ketosis.
It potentially has some effects on the developing fetus or on the nursing child. Anyone with a history of eating disorders, binge eating disorder, anorexia. Cutting out carbohydrates can worsen the cycle and make eating
disorders worse in the long run. – All right so let's talk
about the paleo diet, also affectionately known
as the caveman diet. – Yes. So this was a very popular
diet a few years back, but a lot of people are still, are following this eating plan. And essentially it's sort
of going back to the basics as we would imagine our ancestors years ago would have eaten. And this would really be whole foods, unprocessed foods. Avoiding thing such as dairy
and grains, especially. So it really focuses on protein, especially lean protein
such as fish, chicken, eggs, vegetables, fruits, things like nuts. Even root vegetables
and things like casaba. – And what about meat? – So meat consumption on a paleo plan is considered acceptable, but generally leaner cuts
of meat are preferred.
I usually recommend
grass fed meats as well as opposed to grain fed meats, but it sort of depends on
your level of carbohydrates because if you're eating foods that are higher in
carbohydrates like fruit, carrots, more starchy type vegetables, you really don't wanna be eating
very high fat foods as well because the conjunction of high fat and high carbohydrate foods together can be problemsome. – So who is a good
candidate for this diet? – So a good candidate for a paleo plan would be somebody who enjoys
the foods in the plan, wants to continue it indefinitely, at least a majority of the time.
Because, like I said, anything that's considered temporary and eventually going
back to old eating habits usually result in weight regain. – And what are the health
benefits of this diet? – So the health benefits of eating foods that are whole, natural,
high in vegetables, low in sugar are numerous. One, they can help promote weight loss. And actually I'm sitting in my clinic where I have a sample
of a five-pound fat mass that I sometimes show patients who feel like five pounds
isn't a lot of weight loss, and it really is a lot, and it can be helpful to see a visual demonstration of what the actual area
and volume looks like. But weight loss if a benefit of both keto plans and paleo plans. Really, any diet that's
eliminating calories and easy to stick to can help people lose weight. When people lose weight, their general health
and well being improves. They lower their risk of cancer, high blood pressure, heart disease, diabetes, depression,
sleep apnea, dementia. It goes on and on. – And what about the pegan diet, which is a combination of paleo and vegan? – I've heard of this plan, I haven't yet seen that
many people following it.
It seems to be essentially
a paleo type plan with a focus on plant based food. So really instead of doing more lean meats with the vegetables and fruits, having 75% of daily food intake coming from fruits and vegetables, and only a small amount coming from meat. So more of a plant-based paleo, but still eliminating beans and starches, sugar, dairy foods, and grain products such as wheat or bread.
– And what's the benefit
of this pegan diet? – Essentially similar benefits to paleo or keto type
plan with weight loss, but there is evidence that focusing on more plant-based foods might also help in terms
of cardiovascular risk. So there is a lot of debate out there. I don't think anyone can argue that eating a lot of vegetables and whole foods and avoiding
processed refined food isn't good for your health. – Any final thoughts, doctor? – I would just say, and to remind people that
any type of eating plan really depends on your
personal preferences, what you enjoy eating, what you think you could
continue in the long run because it shouldn't be temporary fix. The data has shown that short term diets usually fail in the long term because people will regress
to their prior eating habits. So definitely think about something that's simple, that's safe, but most importantly sustainable for you that can be continued really indefinitely. – Thanks so much, Dr.
I really appreciate it. Want more information on these diets? Please click on the link or go to Scripps.org/videos. Want more critical
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Scripps Health YouTube channel and follow us on social
media at Scripps Health. I'm Susan Taylor, thanks for joining us. (upbeat music).