Are carbs good or bad for us?
What’s the deal with carbs? Is low-carb the way to go? Are some carbs better than others? Should I avoid all sugars? Are the sugars in fruits and vegetables bad too? What is insulin and why should I care?
I did the low-carb thing. I ALSO did the eat carbs, but avoid sugar thing. Now that I’ve had actual professional education and have read tons of peer-reviewed nutrition research, I STILL believe avoiding refined sugars is part of the key to success in avoiding chronic diseases such as type 2 diabetes and cancer. However, after spending three quarters (basically 8 months) studying biochemistry in great detail I am no longer so afraid of (and confused by) the sugars contained in fresh fruits and vegetables and here I will explain why.
As I’ve mentioned in previous posts and will probably again later, I AM A CONTROL FREAK. For years I avoided sugar, even the sugar in fruits and vegetables. I thought it was all the same. Even when I learned about the glycemic index (GI) it appeared as though foods listed as “high GI” foods such as bananas, prunes, carrots, and beets should be avoided with all cause. The funny thing is the entire time I spent avoiding these phytonutrient-packed, disease-fighting foods I was consuming low-calorie, sugar-free foods such as rice cakes which were causing major insulin spikes in my blood (I’ll explain more about that later) thus causing more fat to be stored. YUK! At that time what I thought of as a typical healthy meal was something really boring such as canned tuna with white potatoes or grilled chicken with white rice and maybe some steamed broccoli. But NEVER did I dare eat any carrots or fruit, because they were the evil sugar-laden foods. Here’s a crazy little story: I remember standing in line at the grocery store one day and felt super guilty because I was buying a peach. A PEACH! SERIOUSLY!
But obviously it wasn’t working for me because for years I was doing the ‘gain ten pounds-lose ten pounds’ thing and even when I was at a good weight I was always struggling to lose those last five pounds. I finally decided that my body had a set point (a commonly hypothesized theory in the nutrition research world known as “the set-point theory“) and gave up trying to lose weight. Then I started my post graduate studies and started learning all about how nutrition correlates with basically EVERYTHING going on in our bodies. Duh. It makes total sense really. And I’m embarrassed now that I spent so many years so focused on my appearance and didn’t give my body the love it deserved.
Okay, so here’s the deal. I was wrong about sugar. The sugar found in plant-based foods is NOT the same as the sugar found in cookies, cakes, pies, and even bread. And for all of the control freaks out there who read all the food nutrition labels and count every gram of sugar they consume regardless of where it comes from I am going to explain this because I understand – you need to know! Note – I think reading food nutrition labels is a FANTASTIC habit to get in. But I’ll get into that in another post that you can read here…
So…obviously I’m not going to teach you all about carbohydrate metabolism in a single blog post. Something important to know about though and consider when making decisions on what to eat is how insulin works in your body. Insulin is a very important hormone and along with glucagon (another hormone which basically has opposing effects to insulin) regulates how the body uses or stores the food you eat. I’ll explain more about insulin and diabetes in another post, but for the purposes of understanding the differences in sugar I will just touch on it briefly here.
What does insulin do?
Well, a lot of things. A LOT! And keep in mind those with diabetes mellitus either do not produce (any or enough) insulin or the insulin they produce does not do what it is supposed to do. For now we will discuss normal metabolism, meaning how insulin works in an individual who is perfectly healthy and everything is working the way it should. Many of you though may be at least a little insulin resistant which could potentially lead to type 2 diabetes, so you need to pay attention!
When you eat any food that is broken down (catabolized) to glucose (any food that has any carbohydrate in it at all) insulin is secreted from the pancreas. Insulin tells body cells to suck up the glucose from the blood so that it can use it for fuel. If more glucose is consumed than is needed it is stored in the form of glycogen (a bunch of glucose molecules stuck together) in muscle or liver tissue. Once those glycogen stores are full the extra glucose is converted to triacylglycerol (fat molecules) and stored as fat.
What about glucagon?
Glucagon’s major job is to make sure that there is enough circulating glucose so that the brain remains fueled. So, when you haven’t eaten a carbohydrate-containing meal in several hours glucagon tells the liver to release some glucose from its glycogen stores into the blood in order to maintain safe levels. This is really important to ensure that the brain has a constant supply of glucose so that it can keep functioning.
So what happens to the fat and protein I eat?
This is where it gets confusing. I’d love to say it’s as simple as what I wrote above, but there’s a lot more detail to it – like I said, I can’t teach you biochemistry in a single blog post. How your body utilizes nutrients all depends on your energy state, how long it has been since your last meal, and what was in your last meal. It is very complicated. I will say this though. If you consume a meal that is in excess of what your body needs and contains all of the major macronutrients (fat, carbohydrates and protein), your glycogen stores will be replenished, your amino acid pool will be replenished and most of the fat you consume will be stored as fat. It is true that our bodies need fat, especially essential fatty acids since our bodies cannot make them, but like I said, if you pig out most of it will likely be stored as fat. Sorry. The extra carbohydrate you consumed that didn’t serve as energy at that particular moment or form glycogen will also be stored as fat. And the extra protein that wasn’t needed to fill the amino acid pool will also be stored as fat. Yep. All the extra is stored as fat.
Okay, so what’s the difference between the carbs in a rice cake and the carbs in an apple?
This is where the glycemic index and glycemic load come into play. You’ve probably heard of the glycemic index. The glycemic index is a measure of how fast blood glucose levels rise after consuming a particular carbohydrate-containing food or meal. It is measured against a standard, usually white bread or pure glucose and compared to the same amount of food in weight, usually 100 grams. For example, the glycemic index for carrots would be based on 100 grams of carrots. That’s a lot of carrots! As you might guess, this is not such a great measurement since you wouldn’t normally eat 100 grams of every type of food – 100 grams of fresh spinach for example is a heck of a lot of spinach! Conversely 100 grams of apple is just a small apple. Or a 100 gram cookie is just a regular sized cookie. That’s why food scientists came up with a more accurate measure of how foods affect blood glucose levels called the glycemic load. The glycemic load is based on serving sizes rather than a set amount of every single food so it makes a lot more sense. You will notice that glycemic load tables differ depending upon the resource. This is because the serving sizes may be different. Overall though, it is a much more accurate measure of how carbohydrate-containing foods affect insulin levels and hence blood glucose levels in our blood.
What does this mean?
When you first look at the glycemic index (GI) of the foods listed in the chart above it would appear that vanilla cake is a healthier choice than quinoa. But when you take into consideration the serving size you see a big difference in the measures of GI and GL. For example, it looks like lentils would be a bad choice (high GI), but they actually have a very minimal effect on blood insulin levels. In other words foods that have a lower GL such as a serving of lentils take longer to break down into simple glucose molecules and enter the blood stream. As soon as a healthy person starts eating a carbohydrate-rich meal insulin is secreted from the pancreas and the glucose in the blood is mopped up very quickly. When the meal contains low GL foods, insulin is secreted more slowly because the glucose enters the blood at a slower rate. On the other hand, if you were to eat a jelly doughnut (a very high GL food) the doughnut would be broken down very quickly and your blood would be flooded with glucose super fast. Your poor little pancreas would have to work hard to shoot out tons of insulin to make sure all of that glucose gets pumped out of the blood and into body cells (and most likely stored as fat). Since the glucose (from high GL foods) enters the blood very quickly, insulin is secreted quickly thus leading to a quick drop in blood sugar. Because of this you become hungry sooner than you would if you had eaten something with a low GL because the glucose levels in your blood are sustained when you eat low GL foods, entering the blood at a slower rate, keeping you satiated longer. SO EAT LOW GL FOODS AS OFTEN AS POSSIBLE!
COMBINING LOW GL FOODS TO HIGHER GL FOODS DECREASES THE OVERALL GL OF THE MEAL
You can combine foods to lower the overall GL of the entire meal. Take for example chocolate brownies. As you can imagine regular chocolate brownies have a very high GL causing your pancreas to shoot out tons of insulin. If you made just a few healthy ingredient swaps in that brownie recipe such as trading the regular sugar for date sugar or date paste, adding some black beans in place of some of the flour used and use whole wheat pastry flour or coconut flour instead of all purpose flour – now the GL of those same, still very delicious brownies just decreased TONS! See! You can still enjoy all of your favorite foods and still be very healthy!!!
What’s the deal with fake sweeteners?
Some research suggests that non-nutritive sweeteners, the term given to “fake sweeteners” cause insulin to react much in the same way that real sugar does. If this is in fact true, then our bodies could end up craving more food in reaction to the fake sweetener found in food causing us to eat more! YUK! Not only that, but some non-nutritive sweeteners have been found to cause cancer in mice. Yes, you would supposedly have to consume a TON of aspartame for you to get bladder cancer (supposedly), but if you are drinking several cans of diet soda per day and other things with aspartame in it…do you really want to take that chance?
Recently a new sweetener (or chemical rather?) called “Sweetmyx” has been developed and manufacturers are planning to use it in place of some of the high fructose corn syrup and sucrose used to sweeten soda and other processed foods. It hasn’t even been studied for very long. Sweetmyx enhances the flavor of soda by stimulating your umami sense much in the same way that monosodium glutamate (MSG) enhances the flavor of cheap Chinese food.What’s the umami sense you ask? Great question! We actually have five, not four senses when it comes to taste: bitter, sweet, salty, sour, and umami. Quoting Elaine Watson of FoodNavigatorUSA.com in an article about this “exciting new sweetener being developed by Senomyx”:
“Building on work by scientists who have successfully cloned human taste receptors for sweet, bitter and umami tastes, Senomyx uses high-throughput biological screening techniques to evaluate millions of molecules to identify which substances bind to specific taste receptors. So far it has programs for sweet, savory, salt reduction, cooling and bitter-blocking, and has struck deals with big names in the industry from PepsiCo and Firmenich to Ajinomoto. ”
DOES THIS SOUND HEALTHY???
The scientists are developing chemicals in a lab to add to processed foods that we (well, not me but you know what I mean) eat.
THIS IS NOT REAL FOOD!
In many people flavor additives and enhancers cause adverse reactions such as headaches, bloating, nausea, or worse! And did you notice the end of the quote? Yeah – it’s all about making money. That’s all anyone cares about. If there was a way to make money off of broccoli and spinach they’d get right on it, but there’s not. Supplement companies already did that. Unfortunately taking specific micronutrients out of healthful foods doesn’t work the same as eating whole foods. But I’ll get in to that in another post…
So should you opt for regular soda instead of diet?
Um…NO!!! First off, the Sweetmyx (or S617 as it’s called by it’s developer, Senomyx) will be added to regular soda from what it sounds like. Not only that, but soda is bad for several reasons (a whole entire post worth of reasons) so you should just cut the habit now! It won’t be easy, but that kind of taste is an acquired or habit-forming craving, so if you slowly make the conversion to drinking plain soda water with fresh lemon and/or lime (wash them thoroughly first), you will start to love this new, refreshing drink. And DRINK MORE PURIFIED FLAT WATER! Your skin will glow, your gastrointestinal tract will function better, and your entire body will be much happier!
What about Stevia?
Stevia (Stevia rebaudiana) is a natural plant that has been used in herbal medicine for the treatment of diabetes, alcohol abuse, and for its antibacterial, anti-inflammatory, antimicrobial, antiviral benefits and also as a digestive aid (although these uses are based on theory and tradition, not medical science). It has however been found to have significant, beneficial effects on blood pressure (BP) in science-based research. This is great for most people, but if you are taking blood pressure lowering medication you should be aware of stevia’s BP-lowering abilities just in case your BP gets too low. Also, stevia may lower blood glucose levels, so those of you who take medications that lower blood glucose levels should be advised. I doubt a little bit of stevia in your coffee is going to do any harm. Just pay attention to your body. For most people the BP and blood glucose lowering effects of stevia will be beneficial.
Another EXTREMELY beneficial effect stevia has on the body is the fact that it is highly alkaline forming. This may not mean much to you now, but you’ll understand just how important consuming an alkaline diet is later when you read my alkaline diet post. Personally, I love stevia. I use it in baking, in my coffee and in my morning oatmeal or oat bran every day. It tastes great too! I much prefer it over regular sugar.
Is it bad that a plant-based diet consists of mostly carbohydrates? Will that lead to high blood sugar and consequently type 2 diabetes (T2DM)?
Absolutely not. In fact, there is STRONG scientific evidence indicating that carbohydrates from a plant-based diet have positive effects on both weight and blood sugar, two important factors that contribute to type 2 diabetes mellitus (T2DM). Most plant foods are low-glycemic load foods because they are loaded with fiber. Additionally, they are loaded with antioxidants and inflammation-fighting phytochemicals that help to ward off chronic disease. One more thing before I leave you with this DELICIOUS recipe that you HAVE to try – Once you start making changes in your sugar intake you will notice major differences in your energy levels. Good changes! Sugar is a proven habit-forming substance. The addiction is terrible. But you can satisfy your sweet tooth with healthier options and forgo the midafternoon crash. You’ll stop getting ridiculously tired an hour after your morning latte and scone and you’ll even start to crave healthy food. FOR REAL! Once you get rid of your addiction you’ll be completely satisfied with and actually crave a bowl full of berries and grapefruit with a little stevia. Heck – sometimes when I’m feeling really crazy I pour a little vodka on top! Whoo hoo!!!
Okay. This is a recipe I found on one of the very first food blogs I started following. I saw the pictures and knew I had to try this recipe. I know the ingredients sound crazy, but trust me. I made just a couple of minor revisions to eliminate the refined sugar, but you can find the original recipe here. Sooooooooooooo delicious!!!!!!!
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- Watson E. Senomyx: first products from collaboration with PepsiCo using sweet taste modifier S617 will be commercialized in 2014. FoodNavigatorUSA.com. http://www.foodnavigator-usa.com/Suppliers2/Senomyx-First-products-from-collaboration-with-PepsiCo-using-sweet-taste-modifier-S617-will-be-commercialized-in-2014 . Published on November 13, 2013. Accessed on May 20, 2014.
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- It’s a pumpkin pizookie! ChocolateCoveredKatie.com. http://chocolatecoveredkatie.com/2011/10/24/its-a-chocolate-pumpkin-pizookie/. Published on October 24, 2011. Accessed on May 20, 2014.