Fructose, a not-so-sweet surprise?

Fructose has earned itself a special spot in the lime-light in the last ten years, and with good reason. One minute you hear fructose is bad, the next you see a commercial saying it's the same as sugar. One day you go to your alternative medicine doctor and they say stay away from the stuff, the next day you do to your medical doctor and they tell you to use agave nectar because it's low glycemic. It's all very confusing! Well, I'm here to help you sort out the facts, the myths, and most importantly, the marketing.

First of all, let's compare fructose to it's cousins, glucose and galactose. Each of these are monosaccharides (one-unit sugars) that contain 6 carbons. These are bound together to form disaccharides (two-unit sugars). Sucrose, table sugar, is a glucose bound to a galactose. Lactose is a glucose bound to a galactose. These are both so called "simple sugars" because only one bond needs to be broken to get back to sugar building blocks, monosaccharides. Starch, like the glycogen in muscle and liver cells, is made up of long strands of glucose molecules bound together for easy storage. Each of these bonds requires slightly different enzymes for digestion, but the end product that makes its way to your cells for energy is going to be one of these three basic sugars.

Fructose is naturally found in fruit, and is by no means an evil sugar all by itself. However, the invention of high fructose corn syrup (HFCS) in the 1970s has made fructose an all too common occurrence in the American diet today. While the Corn Refiners of America may try to bamboozle us into thinking that HFCS is "a natural sugar that comes from corn" and "like sugar, is fine in moderation", I'm here to tell you that these statements could not be further from the truth.

In terms of their caloric value fructose and glucose are practically the same, but there are several things that make fructose a completely different beast in regards to its effects on the human body.

1. The metabolism of fructose is quite different than glucose.  For you biochemistry nerds out there, in his YouTube video "Sugar: The Bitter Truth" Dr. Lustig details the differences between glucose and fructose metabolism [1]. The two main differences (aside from the hormonal interactions) is that almost all of the metabolic burden of fructose falls onto the liver, and that calorie-for-calorie fructose is more readily converted to fat.

2. Fructose affects the body, and it's hormones differently than glucose. Glucose requires the hormone insulin to get into cells, which triggers adipose (fat) cells to release a hormone called leptin. Leptin tells the brain "I've had enough", thus serving as a negative feedback mechanism to prevent over-consumption of sugar. These hormones also suppress the release of another hormone, ghrelin. Ghrelin is a hunger stimulating hormone that is produced in the stomach. Suppressing ghrelin while increasing leptin secretion gives you the feeling of satiety. However, fructose does none of these things, leaving you yearning for more sugar.

3. Perhaps most importantly, marketing for HFCS and fructose containing products such as agave nectar have lead people to believe that they are actually healthy. The Corn Refiners "sweet surprise" commercials [2] and print ads surely paint a convincing picture. By portraying the HFCS skeptic as a uninformed scare-mongers, who after being questioned by what can only be called the HFCS enthusiast can only shrug and mumble, the Corn Refiners have made it quite clear that you should feel silly for simply questioning their product [2]. I much prefer this spoof commercial [3].

Agave nectar is unique in that many well intentioned doctors are now recommending it as a sugar alternative to their diabetic patients. Touting it's shiny low glycemic index label proudly, agave has managed to find itself a nice little niche among those who have diabetes and a desire to follow a low sugar diet, but still crave sugar. The problem is that agave is NOT low sugar- it is low(er) in glucose. According to my searches, agave ranges anywhere from 70-85% fructose, as opposed to HFCS that is typically 55% fructose, or table sugar that is 50% fructose. The reason agave is low glycemic is that fructose does nothing to raise your blood sugar, because "blood sugar" actually means "blood glucose". When blood glucose raises, diabetics have to take insulin (see number 2). Since fructose does not interact with these hormones it is considered better for diabetics, but that could not be further from the truth. The problem is that they fail to tell you on that nice, shiny label that high fructose sweeteners such as agave will leave you wanting more sugar, is more readily converted by fat, places undue burden on the liver, and is, calorie for calorie, still a sugar.

The moral of the story yet again is that you can't trick the body. We should all be on a low sugar diet-  but this means all sugars and all sweeteners. Don't fool yourself any longer- there is no such thing as a healthy sweetener. I'm not saying don't enjoy your sweets every now and then, but sugar is truly something to be consumed in MODEST moderation.

In a previous post we talked about how artificial sweeteners like aspartame create a feeling of disconnect between the stomach and the brain which leaves you craving more sugar, in addition to the very real possibility of causing cancer [4]. Now we have learned that low glycemic sweeteners (aka high-fructose sweeteners) such as agave and HFCS not only leave you craving more sugar, but will make you more fat and stress your liver. I hope you use this information to make the healthiest possible choices in the future.


Too legit to quit,

Nikki Cyr, D.C.


Referenced links:
[1] https://www.youtube.com/watch?v=dBnniua6-oM  <-- More on the metabolism of fructose
[2] https://www.youtube.com/watch?v=lQ-ByUx552s  <--- Commercial funded by the Corn Refiners
[3] https://www.youtube.com/watch?v=hYiEFu54o1E  <--- The real deal!
[4] http://createanewbox.blogspot.com/2012/08/artificially-sweet-part-1-truth-about.html

Other good reads:
[5] http://www.foodrenegade.com/agave-nectar-good-or-bad/
[6] http://articles.mercola.com/sites/articles/archive/2010/01/02/highfructose-corn-syrup-alters-human-metabolism.aspx
[7] http://www.sciencedaily.com/releases/2008/12/081209221742.htm

Solutions for a soda-less life

Bottom line: You've known all along that soda is bad for you.

Everybody knows that soda is terrible for you- it's not rocket science. Yet millions of people drink gallon after gallon of soda every day. So where is the disconnect, here?

The reality is that people won't change until they see the value in that change. Unfortunately, it's all too easy to focus on the here and now, and ignore the future consequences of our actions because they're not tangible yet! In the example of the soda drinker, the benefit (taste) of the sugary soda somehow outweighs the potential health problems in the future, making it harder to find the motivation to change that negative behavior. That is part of my goal with this blog- to bring attention to the future that you are molding for yourself each and every day so that you can no longer forget about it. People place little value on the intangible, distant future until you make it a reality for them today.

The other problem I see with trying to get soda drinkers to kick the habit is that their taste buds have grown accustomed to that level of taste stimulation. I have heard many, many friends and patients complain that they "just can't drink plain water"- "it tastes so plain!"

Taste can be a very real addiction- your taste buds (and brain) have literally become desensitized to what things should taste like after a while. After your taste buds get used to the amount of sugar and salt in soda, everything else will taste especially bland. The good news is that the brain (and taste buds) can and WILL mold to their new environment, and soon you will see that things you once thought were bland actually have quite a bit of flavor! The key is to work our way back to water gradually so you don't go completely insane.

Here are some ideas for soda replacements-

1. While soda in and of itself is NOT HEALTHY, one baby step may be trying stevia flavored soda, Zevia. Again, this is by no means a health food, but it's a step in the right direction on the way back to drinking plain water.

2. Try infusing water with different herbs and fruit- for example, put a little fresh mint and some fresh strawberries in cold water and let sit for a day or two in the fridge. For other recipes and ideas, this website looks like it has some good ideas, or you can try a simple google search for recipes for infused water.

3. A little lemon in water goes a long way. You can also try brewing some green tea, chilling it, and drinking cold with a little bit of lemon. Get creative!

4. Watered down, real juice may serve as another good stepping stone on your way back to drinking water, but beware of many processed juices. Juice "cocktail", etc is usually code for "this product has almost no real juice, and is mostly just high fructose corn syrup and coloring".

5. Again, water is obviously the ultimate goal and should be the source of 90+ percent of your fluids.

Here are some things I personally would encourage you to NOT replace soda with:

1. Milk and milk products. For health concerns I will describe in another post, I personally do not endorse dairy consumption for most people.

2. Juice and juice coctails are sugar-ridden and should be avoided. At least if you eat real fruit you will get the fiber and additional nutrients from the food, but juice is not as healthy as many seem to think it is.

3. Gatorade is almost as bad as soda- it's basically salt water loaded with sugar. While many athletes seem to like it, I think there are healthier ways to replace electrolytes while you work out. Also, I would say that 75% of people I see drinking Gatorade are not actually working out, but they try to pass it off as juice, and therefore a health food. Don't be fooled- Gatorade is not juice, and it is not healthy.


I hope this gives you all a fun starting point to jump into your new soda-free life! Shape your future today, and take charge of your health!

Nikki

Artificially Sweet: The Truth about Aspartame

Aspartame (also known as Nutrasweet or Aminosweet) is a popular sugar substitute that is commonly found in "diet" foods and beverages, most notably, diet soda. Since it's discovery in 1965 and debut into the food supply in 1982, aspartame has made its way into an estimated 6,000 products including baby food, chewable multivitamins, powdered beverage mixes, toothpaste, frozen meals, soda, and gum (1). Currently aspartame is considered to be safe as a non-nutritive sweetener by the FDA, but in the last twenty years there has been much debate over its safety.

The term "non-nutritive sweetener" is an inaccurate way to describe aspartame- non-nutritive implies that the substance passes through the digestive tract unchanged. However, aspartame is readily absorbed and metabolized in the human GI tract into it's three components: phenylalanine, aspartic acid (aspartate), and methanol. Each of these components have their share of bad press, which adds up to one dangerous artificial sweetener. Don't believe me? Read on, dear reader...

Aspartame has has the reputation for being a carcinogen (cancer causative agent) for quite some time, mostly due to the fact that 10% of it's byproduct, methanol, is metabolized to form formeldahyde, a known human carcinogen. However, studies to prove or disprove aspartame's role in cancer have thus far been largely unclear. In 2006 a "mega-experiment" was performed on 1,800 rodents, in which the animals were given various doses of aspartame in their chow from the age of eight weeks until natural death (4). That last part is of crucial importance- All the other studies that were done until that point were done on rodents that were sacrificed (killed) between 104 and 110 weeks of age, which corresponds to about 2/3 of the animals' lifespan. This is important because approximately 80% of human cancers (and animals) are diagnosed in the last 1/3 of the lifespan (5)- so in all the other experiments they were killing the animals before the cancer would have had a chance to develop! In this study the authors found an increase in cancers of various types in doses as low as 400 ppm, which is equivalent to 20 mg/kg body weight. The FDA's acceptable daily intake for aspartame is currently set to 50 mg/kg in the United States and 40 mg/kg in Europe- nearly twice the dose seen to increase cancer risk in this study. Here are the authors comments on their results:
    "The results of this mega-experiment indicate that APM (aspartame) is multipotential
      carcinogenic agent, even at daily doses of 20 mg/kg body weight, much less than than
     currently acceptable intake. On the basis of these results, a reevaluation of the present
     guidelines on the use and consumption of APM is urgent and cannot be delayed."(4)

Artificial sweeteners are commonly seen in "diet" and diabetic friendly foods- everything from diet soda to frozen "diet" dinners. However, there is a large body of evidence that shows a correlation between artificial sweetener use and weight gain (2). Sweet taste enhances human appetite, regardless of caloric value. Actually, the authors of the study I am now referencing go on to say that "inconsistent coupling between sweet taste and caloric content can lead to compensatory overeating and positive energy balance" (2). They believe this is because of the disruption between the two ways our brains interpret food reward. The first starts in the taste buds, then the sweet taste sensory stimulation is perceived by the brain. This is called the sensory part of the food reward. The second part (the postingestive food reward pathway) depends on the metabolic products of the food, which is ultimately relayed to the hypothalamus, the part of the brain that controls the autonomic nervous system. It has been shown that artificial sweeteners do not activate the postingestive pathway, thus giving your brain two conflicting signals about what it just ate. This just goes to show ya, you can't outsmart the body. Furthermore, because of the increased carbohydrate cravings and subsequent weight gain resulting from aspartame ingestion, "aspartame is believed to cause problems in diabetic control" (3). 

(Nikki's note: I personally don't recommend you drink milk either!.. More on that another time.)

For those of you who don't mind the occasional tumor or diabetes, perhaps the effects aspartame might have on your brain will be the one to tip the scale for you. A recent study in the journal of Drug and Chemical Toxicology (1) demonstrated that aspartame significantly reduces the amount of glutathione (remember that really important antioxidant?) and glutathione reductase (the enzyme that "recycles" glutathione) in the rat brain. Granted, this particular study did use a much higher dose than say, the cancer study, but I personally wouldn't want to chance decreasing my precious glutathione.
    "The results of this study indicate that long-term consumption of aspartame leads to an
      imbalance in the antioxidant/pro-oxidant status in the brain, mainly through the
      mechanism involving the glutathione-dependant system." (1) 
In another study the authors found that samples of rat brain tissue that were damaged by aspartame were completely or partially restored to normal upon incubation of glutathione or L-cysteine (a glutathione precursor) (6). A different study outlined the various ways aspartame interferes with normal neurotransmitter synthesis and function (3). Neurotransmitters that may be effected by aspartame include serotonin (most famous for it's role, or lack there of, in depression), dopamine (decreased in Parkinson's disease), acetylcholine (Alzheimer's), and norepinephrine. So, not only does aspartame cause generalized inflammation and depletion of antioxidants in the brain, but it can lead to a multitude of neurological symptoms via it's effects on numerous neurotransmitters.

To add insult to injury, most processed foods have more than one artificial dye or sweetener in them. Several studies have looked at the synergistic effects of artificial sweeteners with each other and artificial colors. In 2006 a study found "significant synergy" between MSG and the food dye Brilliant Blue in various proportions, as well as aspartame and Quinoline Yellow. All four substances decreased neurite outgrowth on their own, but seemed to have a more profound effect when used together (7). Another study looked at the combined effects of MSG and aspartame on disruption of glucose homeostasis (blood sugar regulation) and found that the two did indeed work together (8). Again, both substances increased fat deposition and insulin resistance on their own, but the effects were magnified when the two acted together.

Many skeptics will say that these results are not convincing because they are almost exclusively based on animal (rodent) studies. I agree- humans and rodents are different. For instance, it has been shown that (because of enzymatic differences) test animals are 60 times less sensitive to phenylalanine, 10-20 times less sensitive to methanol poisoning, and 8-10 times less sensitive to aspartic acid and glutamate than us humans (3).

I hope that I have convinced you all to avoid artificial sweeteners, particularly aspartame. Friends, don't be surprised if i take that diet soda away next time we hang out together!

Nikki

References:
(1) M Abhilash "Long-term consumption of aspartame and brain antioxidant defense status" Drug and Chemical Toxicology 2012 (PMID: 22385158)
(2) Yang Q "Gain weight by "going diet?" Artificial sweeteners and the neurobiology of sugar cravings" Journal of biology and medicine 2010 (PMID: 20589192)
(3) P Humphries "Direct and indirect cellular effects of aspartame on the brain" European Journal of Clinical Nutrition 2008 (PMID: 17684524)
(4) Soffritti M "First experimental demonstration of the multipotential carcinogenic effects of aspartame administered in the feed to sprague-dawley rats" (PMID 16507461)
(5) Mead, N. Sour findings on popular sweetener, Enviromental Health Perspectives 2006 vol 114 number 3 pg 76
(6) Simintzi I "L-Cysteine and glutathione restore the modulation of the rat frontal cortex Na+, K+ ATPase activity induced by aspartame metabolites" Food and Chemical Toxicology 46 (2008) 2074-2079 (PMID: 18343556)
(7) Lau K "Synergistic interactions between commonly used food additives in a developmental neurotoxicity test" Toxicological Sciences 2006; 90(1) 178-187 (PMID: 16352620)
(8) Collison KS "Interactive effects of neonatal exposure to MSG and aspartame on glucose homeostasis" Nutrition and Metabolism (London) 2012 June 14;9(1):58 (PMID: 22697049)