Why doesn’t exercise and diet reduce heart disease for diabetics?

That’s a good question after the June 24 issue of the New England Journal of Medicine reported on the failure of long-term diet and exercise to reduce heart disease in diabetics1. It had been known from earlier and shorter studies that diet and exercise in diabetics appeared to generate a decreased risk of cardiovascular disease. This is important since heart disease remains the number-one killer of Americans, and people with diabetes are two to four times more likely to develop heart disease. Since diabetes is becoming epidemic, this would suggest that heart disease should soon begin to escalate. But for exercise and diet have any benefits in any condition, they have to been continued forever. That is the motivation for this 13-year study that started with the best of intentions. However, last year the study was terminated at 10 years since it was clear that there were no cardiovascular benefits. Now that the study details have been published, it is clear why it failed.

First, all of the success of diet and exercise started to evaporate after the first year. Remember, the people who enter these studies are highly motivated with a terrible future awaiting them. So why would they seemingly throw away all the initial benefits of weight loss and reduction of blood sugar? Part of the reason can be explained by why most diet program fail: Willpower can only take you so far if your hormones are working against you. The end result is you are constantly hungry and always tired.

The amount of calories the subjects of this study consumed was low (between 1,200 and 1,800 calories per day), but the diet was a high-carbohydrate diet (that induces low blood sugar due to hyperinsulinemia). The diet was coupled with lots of exercise (that also lowers blood sugar). This is an almost surefire prescription to be constantly hungry and tired. As a result, compliance wanes.

On the other hand, if you are never hungry, then compliance is better. That was the case with another 13-year study of diabetic patients who had gastric bypass surgery. For these patients, there was a significant reduction in cardiovascular events2. The reason is probably hormonal. If you lose weight by diet and exercise, your levels of the hunger hormone ghrelin increases with no change in the levels of your satiety hormone, PYY. Just the opposite happens with gastric bypass surgery. Ghrelin doesn’t change, but PYY increases3. The result is that you are not hungry, and therefor your lifestyle compliance improves.

Of course, giving every diabetic gastric bypass surgery makes little sense. Giving them new, more powerful diabetic drugs with equally powerful side effects (like heart attacks) also makes no sense.

There may be third way: Functional foods that can increase PYY levels. But these have to be tasty (like pasta and rice) and convenient (only 90 seconds to make) since you have to take them the rest of your life. That’s the project I have been working on for the past six years. These new Zone meals may be the answer, as they appear to reduce hunger without causing fatigue while eating the foods you like to eat. Zone meals are low-tech medicine with potentially high-tech results and are coming soon.

References

  1. Wing RR et al. “Cardiovascular effects of intensive lifestyle intervention in type 2 diabetes.” NEJM DOI:10.1056/NEJMoa 1212914 (2013)
  2. Romeo S et al. “Cardiovascular events after bariatric surgery in obese subjects with type 2 diabetes.” Diabetes Care 35: 3613-2617 (2012)
  3. Olivan B et al. “Effect of weight loss by diet or gastric bypass surgery on peptide YY3-36 (PYY) levels.” Ann Surg 249: 948-953 (2009)

New food trends may be dysfunctional

dysfunctional food trendsAs our obesity epidemic gets worse and the general health of Americans continues to decline, people are always searching for new food trends to make us thinner, happier and smarter.

The leading contenders for the next new thing are functional foods. Frankly, these are simply processed foods with added dietary supplements to make you more likely to purchase them compared to the competition on the same shelf. Of course, this means the functional food can’t be too much more expensive than its competitor (and ideally the same price) without affecting the taste of the product. As an afterthought, it might even have some health benefit for you.

Frankly, there are only two functional foods that have been truly successful over the years. The first is Gatorade. Originally developed to reduce minerals lost during exercise, the original Gatorade tasted terrible. So they simply added some sugar to make it taste better and called it a sports drink. Gatorade is basically a Coke or a Pepsi with minerals, but you feel better about yourself when you guzzle down those carbohydrates. The other commercial success was Tropicana Orange Juice with Calcium. The makers of Tropicana didn’t ask you to pay a premium for this functional food since it was exactly the same price as Tropicana Orange Juice without calcium. That’s why the sales of this functional food dramatically increased. Who doesn’t want something extra (and it might even be healthy) for free?

It’s been a long time since any new functional foods tried to break into the market. The two most recent have been POM and Activia yogurt. POM contains polyphenols from the pomegranate seed. That’s good because polyphenols are excellent anti-oxidants and potentially good anti-inflammatory chemicals. But like the minerals in Gatorade, they taste terrible. So when you purchase a bottle of POM, what you are getting is a mass of added sugar. I guarantee you that the intake of these polyphenols in POM is not worth the extra sugar.

Another “new” source of polyphenols we hear about comes from chocolate, which is now being promoted as the new super-fruit (1). Like all polyphenols, the polyphenols found in chocolate are intensely bitter. That’s why no one likes to eat unsweetened Baker’s Chocolate even though it is polyphenol-rich. But if you add a lot of sugar to it, then it tastes great. In fact, it’s a candy bar. Again like most functional foods, these polyphenol functional foods represent one step forward in that you are consuming more polyphenols, but two steps backwards for consuming too much sugar.

Tasting bad is something that has really prevented yogurt sales from taking off in America. The solution was simple. Add more sweetness, usually in the form of fruit plus extra sugar. Finally, natural yogurt became acceptable. But to turn it into a functional food, Dannon decided to add more probiotics to its already sugar-sweetened yogurt and call it Activia, promoting it to help soothe an angry digestive system. In December 2010 the Federal Trade Commission stepped in and hit Dannon with a $21-million fine for false advertising (2). Not only were the levels of probiotics in Activia too low to be of any health benefit, but Dannon was also making drug-claims on a food to boot. Not surprisingly, the FTC is also after POM for similar misleading claims (3). Darned those regulators. They take all the fun out of marketing functional foods.

The list goes on and on. Whether it is vitamin waters, or micro-encapsulated fish oil, vitamin D, etc., trying to put bad-tasting nutritional supplements that have some proven benefits into foods and charge the consumer a higher price is never going to work. To prevent the poor taste, you have to microencapsulate the supplement to make it sound high-tech, (they call it nanotechnology) and this costs a lot of money. Adding the bad-tasting nutritional supplement without the microencapsulation to a food makes it taste worse (unless you are adding a lot of sugar at the same time, of course eroding all the potential health benefits of the supplement). Finally, the consumer will only buy this new functional food if it is the same price as what they usually purchase.

So what’s the next new thing in functional foods? In my opinion, it is returning to the concept of cooking for yourself in your own kitchen using food ingredients you buy on the periphery of the supermarket, and then taking the nutritional supplements that have proven efficacy (like fish oil and polyphenols) at the therapeutic level to produce real health benefits. Now you have real functional foods that finally work at a lower cost than you would pay for in the supermarket.

Now, that’s a radical new food trend that just might work.

References

1. Crozier SJ, Preston AG, Hurst JW, Payne MJ, Mann J, Hainly L, and Miller DL. “Cacao seeds are a ‘super fruit’: A comparative analysis of various fruit powders and products.” Chem Central J 5:5 (2011)

2. Horovitz B. “Dannon’s Activia, DanActive health claims draw $21M fine.” USA Today. December 15, 2010

3. Wyatt E. “Regulators Call Health Claims in Pom Juice Ads Deceptive.” New York Times. September 27, 2010

Nothing contained in this blog is intended to be instructional for medial diagnosis or treatment. If you have a medical concern or issue, please consult your personal physician immediately.