Is Soda One of The Causes of Arthritis?

Written by Dr. Steve Chaney on . Posted in current health articles, Health Current Events, Healthy Lifestyle

is soda one of the causes of arthritis

Author: Dr. Stephen Chaney

 

Recently, I came across an article which claimed an association between soda and arthritis.  So, is soda one of the causes of arthritis?  In previous health tips from the professor I have shared that soda consumption can cause weight gain  and heart disease . As if that weren’t reason enough to avoid sodas, recent headlines suggest that sodas can also cause rheumatoid arthritis. That is a pretty strong claim, so let’s look at the study behind those headlines.

Do Sodas Cause Arthritis?

This study (Hu et al., American Journal of Clinical Nutrition, 100: 959-967, 2014) followed 79, 570 women enrolled in the first Nurse’s Health Study (NHS) and 107,330 women enrolled in the second Nurse’s Health Study (NHS II) – that’s a total of 186,900 women – for at least 20 years. The women were aged 25-55 at the beginning of the studies and 857 of them developed rheumatoid arthritis over the next 20+ years.

All of the participants in the study filled out a questionnaire covering medical history, lifestyle and chronic disease at entry into the study and every two years afterwards. Compliance to this protocol was >90%, which is excellent for this type of study. The results were pretty impressive:

· Women who consumed ≥ 1 serving of sugar sweetened soda/day had a 63% higher risk of developing rheumatoid arthritis compared to women who consumed no sugar sweetened soda or consumed < 1 serving/month.

· The association between sugar-sweetened soda consumption and rheumatoid arthritis was much stronger for late-onset rheumatoid arthritis than it was for early-onset rheumatoid arthritis. When the authors restricted their analysis to women who developed rheumatoid arthritis after age 50, consumption of sugar sweetened sodas was associated with a 2.64-fold higher risk of developing rheumatoid arthritis (That’s a 264% increase).

· The type of sugar did not appear to matter. Sodas sweetened with sucrose and high-fructose corn syrup were equally likely to increase the risk of rheumatoid arthritis.

· There was no association between diet soda consumption and rheumatoid arthritis.

 

What Are The Strengths and Weaknesses Of The Study?

Strengths of The Study: The strengths of the study are fairly obvious.

This was a very large study and the effects (64%) and (264%) were also large. Those aren’t trivial differences. The size of the study and the magnitude of the effects bolster confidence in the outcome of the study.

Weaknesses of The Study:

This type of study measures associations. It doesn’t prove cause and effect. Therefore, the headlines saying “Soda Consumption is Associated With Arthritis” are more accurate than those saying “Sodas May Cause Arthritis”.

In studies of this kind we can never be sure whether the variable that was measured (soda consumption in this case) was responsible for the outcome or whether it was some other variable that wasn’t measured that was responsible for the outcome. In particular, the women who developed rheumatoid arthritis were also more likely to:

arthritis· Have lower incomes.
· Exercise less.
· Have higher energy (calorie) intake.
· Have poorer diets.
· Take fewer multivitamins and other supplements.

The authors tried their best to compensate for these differences statistically, and the fact that the very large effects of soda consumption on rheumatoid arthritis occurrence were not significantly affected when these differences were taken into account adds confidence to their conclusions. However, it is never possible to exclude the possibility that some other variable they did not measure was responsible for the increase in rheumatoid arthritis.

Are Diet Sodas Off the Hook?  Or,could They Be One of The Causes of Arthritis?

Could diet sodas be one of the causes of arthritis?  This study showed no association between diet soda consumption and rheumatoid arthritis. Previous studies have suggested that diet sodas don’t increase the risk of heart disease to the same extent as sugar-sweetened sodas. Does that mean that you should just start drinking diet sodas rather than sugar sweetened sodas?

diet sodas and arthritisThe answer is probably not. As I have pointed out in an earlier issue of “Health Tips From the Professor” , and has been confirmed by a recent meta-analysis of 24 clinical studies (Miller and Perez, American Journal of Clinical Nutrition, 100: 765-777, 2014), double blind studies in which all other caloric intake is carefully controlled generally show that people tend to gain slightly less weight when consuming diet sodas than when consuming sugar sweetened sodas.

But in the real world, people consuming diet sodas are just as likely to be overweight as people consuming sugar sweetened sodas. People seem to compensate for the calories saved with diet sodas by consuming more Big Macs, Mrs. Fields cookies and extra large Stabucks Lattes. In the real world, water is the only non-caloric beverage that is actually associated with lower weight.

Is It Enough To Just Stop Drinking Sodas?

I have often paraphrased that famous line from Western movies: “Just put down that soda and back away, and nobody gets hurt”. But is it that simple? Can you prevent rheumatoid arthritis just by drinking less soda?

Once again, the answer is probably no. There are a number of factors that can increase your risk of developing rheumatoid arthritis. Experts will tell you that the causes of rheumatoid arthritis are largely unknown, but that genetic predisposition, smoking and excessive alcohol use can increase your risk.

However, because rheumatoid arthritis is an inflammatory disease I would add overweight; diets high in animal protein, saturated fats, trans fats and sugar; food allergies; gut health issues; stress & exhaustion and chronic infections – and lack of fresh fruits and vegetables, omega-3 fatty acids and regular exercise.

The clinical study I described above found that soda consumption was much more strongly associated with late onset rheumatoid arthritis than early onset rheumatoid arthritis. Based on those data I would speculate that early onset rheumatoid arthritis may be more strongly influenced by genetics and other lifestyle factors, whereas late onset rheumatoid arthritis may be more strongly influenced by sugar sweetened sodas and other sugary foods. Only time will tell if my hypothesis is true.

Is soda one of the causes of arthritis?

The Bottom Line:

1) A recent study reported that women who consume ≥ 1 serving of sugar sweetened soda/day have a 63% higher risk of developing rheumatoid arthritis compared to women who consume no sugar sweetened soda or consume < 1 serving/month.

2) The association between sugar-sweetened soda consumption and rheumatoid arthritis is much stronger for late-onset rheumatoid arthritis than for early-onset rheumatoid arthritis. For women who first develop rheumatoid arthritis after the age of 50, consumption of sugar sweetened sodas is associated with a 2.64-fold higher risk of developing rheumatoid arthritis (That’s a 264% increase).

3) The type of sugar does not appear to matter. Sodas sweetened with sucrose and high-fructose corn syrup are equally likely to increase the risk of rheumatoid arthritis.

4) There was no association between diet soda consumption and rheumatoid arthritis. However, this does not mean that diet sodas are a good thing. Consumption of diet sodas is just as likely to be associated with obesity as is consumption of sugar sweetened sodas, and some recent studies suggest that consumption of diet sodas is associated with high blood pressure.

5) This was a very large and well done study, but it only measures associations, not cause and effect. Further studies will be needed to confirm this observation. However, we already know that sodas are bad for us. This may be just one more reason to minimize our consumption of sodas.

6) We shouldn’t assume that we can prevent rheumatoid arthritis by simply cutting sodas out of our diet. Arthritis has multiple causes (see article above). We should aim for a healthier overall lifestyle if we wish to reduce our risk of developing rheumatoid arthritis and other diseases.

7) Osteoarthritis is much more common than rheumatoid arthritis. This study did not include women with osteoarthritis, so it is uncertain whether these results will apply to osteoarthritis as well.

8) Men are much less likely to develop rheumatoid arthritis than women, so it will be difficult to do a comparable study in men. However, it is likely that the same association between soda consumption and rheumatoid arthritis would be seen in men as well.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

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Comments (1)

  • Jame Thornburgh

    |

    Hi.
    Thought. this was an interesting. article science based. If one reads the doctor’s
    Credentials he appears to basse his articles in sceince nkot fads
    lovw you mom

    Reply

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Latest Article

High Protein Diets and Weight Loss

Posted October 16, 2018 by Dr. Steve Chaney

Do High Protein Diets Reduce Fat And Preserve Muscle?

Author: Dr. Stephen Chaney

Healthy Diet food group, proteins, include meat (chicken or turkAre high protein diets your secret to healthy weight loss? There are lots of diets out there – high fat, low fat, Paleolithic, blood type, exotic juices, magic pills and potions. But recently, high protein diets are getting a lot of press. The word is that they preserve muscle mass and preferentially decrease fat mass.

If high protein diets actually did that, it would be huge because:

  • It’s the fat – not the pounds – that causes most of the health problems.
  • Muscle burns more calories than fat, so preserving muscle mass helps keep your metabolic rate high without dangerous herbs or stimulants – and keeping your metabolic rate high helps prevent both the plateau and yo-yo (weight regain) characteristic of so many diets.
  • When you lose fat and retain muscle you are reshaping your body – and that’s why most people are dieting to begin with.

So let’s look more carefully at the recent study that has been generating all the headlines (Pasiakos et al, The FASEB Journal, 27: 3837-3847, 2013).

The Study Design:

This was a randomized control study with 39 young (21), healthy and fit men and women who were only borderline overweight (BMI = 25). These volunteers were put on a 21 day weight loss program in which calories were reduced by 30% and exercise was increased by 10%. They were divided into 3 groups:

  • One group was assigned a diet containing the RDA for protein (about 14% of calories in this study design).
  • The second group’s diet contained 2X the RDA for protein (28% of calories)
  • The third group’s diet contained 3X the RDA for protein (42% of calories)

In the RDA protein group carbohydrate was 56% of calories, and fat was 30% of calories. In the other two groups the carbohydrate and fat content of the diets was decreased proportionally.

Feet_On_ScaleWhat Did The Study Show?

  • Weight loss (7 pounds in 21 days) was the same on all 3 diets.
  • The high protein (28% and 42%) diets caused almost 2X more fat loss (5 pounds versus 2.8 pounds) than the diet supplying the RDA amount of protein.
  • The high protein (28% and 42%) diets caused 2X less muscle loss (2.1 pounds versus 4.2 pounds) than the diet supplying the RDA amount of protein.
  • In case you didn’t notice, there was no difference in overall results between the 28% (2X the RDA) and 42% (3X the RDA) diets.

Pros And Cons Of The Study:

  • The con is fairly obvious. The participants in this study were all young, healthy and were not seriously overweight. If this were the only study of this type one might seriously question whether the results were applicable to middle aged, overweight coach potatoes. However, there have been several other studies with older, more overweight volunteers that have come to the same conclusion – namely that high protein diets preserve muscle mass and enhance fat loss.
  • The value of this study is that it defines for the first time the upper limit for how much protein is required to preserve muscle mass in a weight loss regimen. 28% of calories is sufficient, and there appear to be no benefit from increasing protein further. I would add the caveat that there are studies suggesting that protein requirements for preserving muscle mass may be greater in adults 50 and older.

The Bottom Line:

1)    Forget the high fat diets, low fat diets, pills and potions. High protein diets (~2X the RDA or 28% of calories) do appear to be the safest, most effective way to preserve muscle mass and enhance fat loss in a weight loss regimen.

2)     That’s not a lot of protein, by the way. The average American consumes almost 2X the RDA for protein on a daily basis. However, it is significantly more protein than the average American consumes when they are trying to lose weight. Salads and carrot sticks are great diet foods, but they don’t contain much protein.

3)     Higher protein intake does not appear to offer any additional benefit – at least in young adults.

4)     Not all high protein diets are created equal. What some people call high protein diets are laden with saturated fats or devoid of carbohydrate. The diet in this study, which is what I recommend, had 43% healthy carbohydrates and 30% healthy fats.

5)    These diets were designed to give 7 pounds of weight loss in 21 days – which is what the experts recommend. There are diets out there promising faster weight loss but they severely restrict calories and/or rely heavily on stimulants, they do not preserve muscle mass, and they often are not safe. In addition they are usually temporary.  I do not recommend them.

6)    This level of protein intake is safe for almost everyone. The major exception would be people with kidney disease, who should always check with their doctor before increasing protein intake. The only other caveat is that protein metabolism creates a lot of nitrogenous waste, so you should drink plenty of water to flush that waste out of your system. But, water is always a good idea.

7)     The high protein diets minimized, but did not completely prevent, muscle loss. Other studies suggest that adding the amino acid leucine to a high protein diet can give 100% retention of muscle mass in a weight loss regimen – but that’s another story for another day.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

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