Science

Cortisol – A Love Story?

Cortisol is one of those hormone buzz words that is making its way around the diet industry right now, especially in respect to how it helps or hinders fat loss. People advocate for a stress free lifestyle in hopes that you lower your cortisol levels, or talk about exercising during the morning or the night depending on your cortisol levels, or even not eating breakfast because of its effect on cortisol. I think before you make a decision on what to believe, you should get a little more information about cortisol and what exactly it does.

Cortisol is a hormone that comes from the adrenal glands, which are located right above the kidney. It really has a few main functions: raise blood sugar through gluconeogenesis (making “sugars” for your body to utilize when it doesn’t have any carbs immediately), to suppress the immune system (which is why you use them with some allergic and autoimmune conditions), and also to help with fat, protein and carbohydrate metabolism.

When the diet industry is talking about cortisol they usually are referring to its role in gluconeogenesis and glycogenolysis (breaking down glycogen, the stored form of carbohydrates in the liver, for energy). This is where things get tricky – cortisol can both help and hinder these scenarios. For example, long-term elevations in cortisol can lead to muscle wasting. While cortisol does break down fat, it’s also shown in some conditions to SUPPRESS the break down of fat.

Like stated above, cortisol is released in times of stress. If you’re running away from a bear cortisol is one of the hormones that tells your body to stop digesting your food and start running…fast. Cortisol is also a hormone that tells your body it’s time to wake up, which is why it’s highest in the morning.

Cortisol literally has a hand in every body system you can think of. From counteracting insulin to controlling diuresis, cortisol is involved. When you’re reading studies or claims about how cortisol will help or hinder your lifestyle don’t think of cortisol as a bad hormone. Remember instead that hormones exist in a balance in our system and we must pay close attention to how they make us feel. If you feel like you have a medical problems that may be related to excessively high or excessively low cortisol it’s important to contact your doctor and schedule an appointment.

Remember, like anything there are no “good” or “bad” hormones, foods, etc. there are only imbalances in the system.

July 15, 2013 Nutrition, Science, , , Read more >

Are stress and a lack of sleep sabotaging your weight loss goals?

A lack of sleep and an excess of stress could be contributing to the stall in your weight loss or fitness goals. Studies have shown that an increase in stress actually increases your blood pressure, which in turn prompts some people to retain a small McDonalds fry worth of salt. Additionally, a lack of sleep has been linked to an increase in the amount of appetite regulating hormones.

We all know that sleep is important. When we don’t get enough of it we’re groggy, unable to concentrate and quick to anger. It turns out that the effects of sleep loss doesn’t stop there. It’s been reported that a lack of sleep also increases the “hunger hormones” in your body, such as ghrelin. Because of this, your body is stimulated to feel hungry more times during the day than someone who received a full nights sleep.

So how much sleep do you need? 

Like everything else, the amount of sleep you need is an individual experience. Experimenting with your body is the only way to determine how many hours of sleep you need to feel your best.

It’s also important to note that the study didn’t just talk about the amount of sleep, but the quality of sleep. Even if you sleep 12+ hours a day, if you’re constantly being woken by other distractions then the quality of sleep is to blame, not just the quantity.

What about stress? Stress can release cortisol, a hormone that has a pretty bad rep because of its role in weight gain. Inappropriate cortisol release caused by stress can cause a gain of visceral body fat, particularly in your abdomen, and cause a decrease in leptin (the “I’m full” hormone). The study mentioned above also points to the possibility of retaining salt because of high blood pressure if you have a certain genetic factor. The combined effect of stress plus high blood pressure lead to retention of up to 1,500 mg of salt a day, which in turn kept blood pressure high even during sleep.

Stress plus a lack of sleep can definitely contribute to obesity, increased appetite, high blood pressure and a general loss of interest in reaching your goals.

What are some ways to get more sleep?

  1. Turn your bedroom or bed into a “sleep cave.” The only time you should be in bed is to sleep. Your bedroom should be free of external stimuli, such as computers or televisions. The room should be dark, not too hot and not too cold, and your bed itself should be comfortable enough to allow for uninterrupted sleep.
  2. Eliminate nighttime distractions. Always use the restroom before bed, put in ear plugs if others are on a different sleep schedule, use blackout curtains to prevent early more sunlight, and other small tweaks to assure your sleeping area is always sleep friendly.
  3. Meditate, do yoga, take a warm bath, drink warm tea, etc. before going to bed to calm your mind.
  4. Avoid caffeine, exercise, or any other stimulatory activity before bed (unless you find these things help you to sleep).
  5. Some people find soothing music to help them fall asleep, others find it a distraction. Find what works for you and stick with it!

Ways to eliminate stress

  1. Identify your stress and try to eliminate or minimize it. Some stress is unavoidable, some of it is unnecessary. Find what you can fix and focus on that.
  2. Surround yourself with supportive people and supportive thoughts.
  3. Enlist the help of others. We often rely on ourselves for everything (If you want something done right, do it yourself, right?) and by allowing others to help us we can truly minimize our stress.
  4. Meditation, yoga, exercise, long baths, and other activities that allow “you time” can help reduce stress.

December 19, 2012 Fat Loss, Science Read more >

Check your “facts” before you spread them

While this blog is dedicated mostly to weight loss and the science of health and fitness, I sometimes stray from that topic to include some important basics involving any type of science. We’ve all read Tumblr articles that are in direct conflict with each other. For example, how many people have written articles about how important protein is, only to be countered by how protein in high quantities is horrible? If you ever find a new fact and you’re not really sure about it, there’s a lot of ways to fact check.

Let’s break down a theoretical fact.

According to a recent survey, most people prefer cats.

Pretty harmless fact, right? You may personally disagree, or agree, but that’s not the point. How do we break down this fact and see if it’s accurate or not?

1. Where’s it coming from?

Let’s say the person who posted this fact gives us a source and we find that the Cat Lover’s Association did this survey. Right off the bat we can see a conflict of interest. Of course the Cat Lover’s Association is going to find that people prefer cats to dogs. What if the group that funded the survey was Animals of America? Sounds a bit more reasonable, right? Just in case you should search deeper into that organization. Turns out the founder and president of Animals of America is actually a member of the Pretty Persian Club and owns three cat hospitals that are just for felines! Another source of bias. Let’s say the survey was put on by Happy Pet Owners of America. We look into the group and see that it’s run by a mix of cat and dog owners, as well as a fair amount of bird, hedgehog and horse people. Definitely something we can trust more. Apply this to any other fact: who did the study, who are they tied to, and do they have anything to gain/any bias by the results of the survey.

2. How did they do it?

Let’s say this survey was conducted by asking people coming out of a pet store. Seems like a reasonable place to survey people about what kind of pets they like, right? What if the pet store was a pet store that only had cats? What if they asked people coming out of a common grocery store? Take a look at HOW they conducted the survey and see if there’s any bias behind it. Did they ask every person who they saw, or just every other? Women only? Men only? Really break it down and take a look at how they conducted the survey. Surveys that involve polls online can be tricky because not everyone fills them out. This is a huge issue when news stations or TV stations do surveys, because only people who view that station will answer the survey. If Animal Planet does a survey about animals they’ll get different results about certain questions than The Hunting Network.

3. How many people were surveyed?

Let’s say they asked 5 people. 5 people! That’s NOTHING! 3 of those people could have been related and have a lot in common with their preferences. If they asked 5,000 people at 100 stores across the nation you’re going to have a more accurate tally of if people prefer cats or dogs. If surveys have a large amount of people surveyed it’s going to have a wider array of opinions and get a better idea of the “average person.”

4. Where was the survey conducted?

Some surveys are asked in other countries or in certain areas of the country that can give very different answers. For example, in some countries cats are not really “domestic.” People use cats to catch rats, not as a pet. Their opinions on the usefulness of cats may differ from someone who has a lot of birds and sees cats as a threat to the natural environment for the birds. Likewise, people who live near the ocean may answer surveys saying they like seafood best versus people who live very far inland and prefer beef or vegetables. The location of the survey is important.

5. What question was asked?

This is very important! What if the question was, “Do you prefer cats or dogs?” There are only two possible answers to this question. People who prefer anything other than cats or dogs won’t chose the animal they prefer. Here are other questions that could have been asked…

“Are cats your favorite animal?”

“Do you like dogs?”

“Do you think cats are pretty?”

“Do you think cats are useful?”

Sometimes people will ask these questions and come to their own conclusion about it. What does it mean to “prefer” an animal? If people answer that they do, indeed, think cats are useful they may interpret that are “Most people prefer cats.” Others may say, “Most people thought cats were useful” or “People find cats to be able hunters.” Make sure that the question that is asked parallels the conclusion the survey came to.

6. When did the survey take place?

“According to a recent survey…” is very vague. What is recent? 6 months? 1 year? 10 years? A survey that takes place in 1997 may have different results than one taken in the last few weeks, especially when you’re asking questions about technology.

7. Their sources.

Surveys and studies often cite other sources when they submit their papers. Scroll down to the end of the study to see where they got a lot of their research from and ask yourself the above questions.

Now that you know the many ways “facts” can be interpreted, start using this any time you see a new “fact.” This will help you to become informed and allow you to make your own decisions about what you hear or read.

July 4, 2012 Science Read more >

Fasting, cheating and other big bears

So this entire series has focused on the myths around your metabolism. I’ve shown that you don’t need to eat every few hours, that you can exercise fasted, that you can fast, that low calorie diets won’t kill all your muscle…but I’ve forgotten an important aspect of all of this. Even though I consider myself an uber-nerd scientist first and foremost, I do understand and acknowledge that there is an element most of us nerds forget: the human element. If it were as easy as fasting once a week, exercising, eating into a deficit to lose weight, wouldn’t everyone be strutting around Kate Moss style? There’s obviously something missing – and I’ve hit on it before, but now I’m going all in baby.

Not eating sucks.

Yep. Not eating sucks. Not eating a giant slice of cheesecake even though you want to makes you crave cheesecake. I showed before that it takes like 5 freaking weeks for your cravings to diminish on low calorie diets. Plus, one of the studies I cited was a little iffy because women cheated! CHEATED! You’re in a scientific study and you can’t adhere to a diet? This is what I call the “Human Element of Science.” It’s the part where your brain tells your body something that may or may not be true.

How about the craving studies? Let’s put this together. You’re on a low calorie diet. To meet all your nutritional needs, you need to eat food that is high in proteins and vitamins – this means no cake. You crave cake. You WANT cake. You crave cake for 5 weeks. Your friends are all going out to eat dinner at your favorite restaurant – the same one with the 400 calorie drinks you down like water – so you can’t go. Your social life starts to disappear because you have a strict diet to adhere to, all while juggling cravings and – depending on how low calorie a diet you have – an eventual decrease in metabolism. Sounds like a crappy way to go.

What about hunger? If your body only “needs” a certain amount of calories, why do people overeat? I’ll compare two studies from before (http://www.ncbi.nlm.nih.gov/pubmed/19943985 and http://www.ncbi.nlm.nih.gov/pubmed/18053311). One study measured the hormones that tell you you’re hungry and found that eating twice a day had the same level of both as those who ate three times a day. However, the second study ASKED people if they were hungry, and people who ate 2 times a day SAID they were hungry more often than the people who ate 3 times a day. Notice the difference? I’m sure a psychologist could delve into this super deep and tear apart why someone may THINK they’re hungry despite biological evidence showing them that they’re NOT hungry, but I think you and I can guess pretty accurately. When noon rolls around my stomach growls, regardless of how many cupcakes I downed between breakfast and then, because it’s time to eat. Am I hungry? There’s no possible way. This is the human element.

And, last but not least, my favorite study – the Minnesota Semi-Starvation Study. After 6 months of this restrictive diet the men became crazy about food. They thought about food a lot, planned their meals, thought about food, talked about food…their life revolved around food. This is a dramatic change from their original personalities. They binged, hoarded, became recluses…it created an unhealthy relationship with food. I think a lot of us can relate to this. I’m sure we can remember – with sad fondness – times when we didn’t know the calorie content of every food or times when food was just food. Dieting can change all of this.

So while I can parrot out all these cool sciency-facts about losing fat by not eating over maintenance and low calorie diets and blah blah blah I’m ignoring the fact that this really doesn’t work for everyone. We have lives, needs, preoccupations, etc. Losing weight is tough. It can be lonely, bland and obsessive. Without adding your own “Human Element” into these facts you’ll find yourself no better off than the Minnesota Semi-Starvation Study men: dreaming of food instead of sex.

July 4, 2012 Metabolism Series, Science, Read more >

What is the Thermic Effect of Food?

The thermic effect of food is the small increase in BMR that happens when you eat. It’s the main drive behind the “eat 4-6x a day” because the theory is that if you eat 6 times a day you’re causing a “spike” in BMR 6x a day versus 3x a day. However, this is grossly misunderstood. The “spike” is directly related to the amount ingested.

Say we have two people eating 3000 calories a day – one person eating 1,500 calories twice a day and one eating 600 calories 5 times a day. Let’s also pretend these people have a TEF (thermal energy of food) of 10%. The first person burns 150 calories twice a day with the spike, the other 60 calories 5 times a day. Both burn 300 calories from the thermal effect of food.

It differs when the calorie count differs – but then your weight loss is based on calories, not the thermal effect of food. Yeah, someone eating 3,000 calories a day burning 300 is burning more than someone eating 2,000 calories a day burning 200. That’s not because they’ve increased their frequency of the meal, but because they’ve increased their calorie count.

July 4, 2012 Metabolism Series, Nutrition, Science, Read more >