Can Genetics Predict Which Diet is Best For You?

Written by Dr. Steve Chaney on . Posted in Genetics and Diet

Author: Dr. Stephen Chaney

 

genetix and dietIt is so confusing. The weight loss claims for popular diets sound so convincing, but they can’t all be true.

The low carb proponents give impressive metabolic arguments for why their diet works best. (Of course, you aren’t a biochemist. You have no idea whether they are speaking the truth or just trying to pull the wool over your eyes.) They quote clinical studies and offer testimonials that “prove” their diet works.

Other “experts” tell you that is nonsense. Your diet needs to be individualized to fit your genetic and metabolic profile. Who do you believe? Do low-carb or low-fat diets work better? Are individualized diet plans the solution?

Fortunately for you a recent study (CD Gardner et al, JAMA, 319: 667-679, 2018 ) has answered your questions. Let me start with some background to put this study in perspective. Then I will describe how the study was done, the study results, and what this study means for you.

 

What Did We Already Know About Diets?

The studies that low-carb proponents quote to “prove” the success of their diet approach are misleading because:

  • Most of the studies are short-term. This is misleading because low-carb diets lead to an initial loss of water weight that is not seen with low-fat diets.
  • Most of the comparisons are done with the typical American diet (which is high in sugar, refined carbohydrates, and junk food) rather than a healthy low-fat diet.
  • Note: This is the short version. I cover this in more detail in my new “Slaying The Food Myths” book.

In contrast, there have been numerous studies comparing the effectiveness of low-carb versus low-fat diets long term (12 months or more). These studies have not found a dimes worth of difference between the two diets. Weight loss was virtually identical.

genetix and diet bestThat has led some weight loss experts to point out that any “one size fits all” diet fails to account for individual variability. They point out that while average weight loss on a particular diet might be 12-15 pounds, some people will have lost 45 pounds and others gained 5 pounds. That has led to research efforts to discover biomarkers that could predict which diet will work best for you. Let me share the two most promising approaches.

A DNA testing approach measures genetic variation in the PPARG, ADRB2, AND FABP2 genes [Don’t worry. There won’t be a quiz.] These are genes involved in fat and energy metabolism. Animal studies have suggested that genetic variation in these genes might be useful in predicting whether individuals respond better to a low-fat or low-carb diet. One preliminary clinical study has suggested it may work for humans as well.

An insulin sensitivity approach measures insulin levels 30 minutes after a glucose challenge (a measurement called INS-30). Some small clinical studies have suggested this approach might also have value in predicting the success of low-carb versus low-fat diets for weight loss.

Unfortunately, some companies are already promoting individualized diet plans based on DNA testing and insulin sensitivity measurement – even though the clinical support for the predictive power of those tests is very preliminary at present.

The current study was designed to compare the effectiveness of healthy low-carb and low-fat diets on weight loss. In addition, it evaluated whether either DNA testing or insulin sensitivity measurements could effectively predict whether individuals lost weight better on low-fat or low-carb diets.

How Was This Study Done? 

genetix and diet studyThis was an excellent study. In fact, it is one of the best studies comparing weight loss diets I have seen in recent years. It enrolled 609 middle-aged (average age = 40), overweight (average BMI = 33) adults from the San Francisco Bay area in a 12-month weight loss study. Here was the breakdown of participants:

  • 57% were women, 43% were men.
  • 40% had a DNA pattern considered favorable for a low-fat diet, 30% had a DNA pattern considered favorable for a low-carb diet (30% had an intermediate DNA pattern that did not predict either low-carb or low-fat).
  • 67% had insulin sensitivity values considered favorable for low-carb diets, 33% had insulin sensitivity considered favorable for a low-fat diet.

The study participants were randomly assigned to either the low-carb diet group or low-fat diet group by a computerized protocol that assured DNA patterns and insulin sensitivity were equally distributed across the two groups.

In contrast to many earlier studies, both groups followed a relatively healthy diet. They were instructed to:

  • Maximize vegetable intake.
  • Minimize intake of added sugars, refined flours, and trans-fats.
  • Focus on whole foods that were minimally processed, nutrient dense, and prepared at home whenever possible.

The participants were not advised to restrict their calories. However, they were given an extraordinary degree of support. They were further divided into groups of 17 that met a total of 22 times over the 12 months with a registered dietitian who provided instruction, support and encouragement. That level of support assured that the participants stuck with their diet for the full 12-month period.

 

Can Genetics Predict Which Diet Works Best?

genetix and diet works best Participants in the study lost an average of 12 pounds. That is not a huge amount of weight, but it is enough weight loss to make a difference, and it is consistent with the results of most long-term studies. When the results were broken down further:

  • There was no significant difference in weight loss between the low-carb group and low-fat group at 12 months. This is consistent with multiple previous studies.
  • Both diets were equally effective at improving lipid profiles and lowering blood pressure, insulin, and blood sugar levels. This is the dirty little secret that many low-carb enthusiasts don’t tell you. The improvements seen in health parameters such as lipids, blood pressure, insulin, and blood glucose are due to the weight loss, not whether the diet is low-carb or low-fat.
  • Neither the DNA pattern or insulin sensitivity offered any predictive value as to whether a low-carb or low-fat diet was more effective for weight loss.

That does not mean that DNA testing is of no value. It simply means that the human genome is far more complex than the companies offering DNA tests have assumed. There will be a day when we know enough to individualize diets based on DNA testing. That day is not now.

What Does This Mean For You?

Forget the weight loss claims of the low-carb enthusiasts. Ignore companies that promise they can select the best diet approach for you based on some simple DNA tests and/or measurements of insulin sensitivity.

This study does not provide definitive answers, but it hints at the weight loss tips that really matter:

  • Ditch the sodas, sweets, fast and processed foods. Instead focus on whole foods, primarily fruits and vegetables, whole grains, and legumes.
  • If you wish to follow a low-carb diet, choose one that is primarily plant-based  rather than meat-based.
  • Focus on what you are eating rather than on calories.
  • Find a group to provide support and encouragement. It doesn’t need to be some expensive diet program. It could just be a group of friends who agree to provide each other with support, encouragement, and accountability.

I cover this topic in much more detail in my new book “Slaying The Food Myths”.

 

The Bottom Line:

 

A recent study compared the effectiveness of healthy low-carb and low-fat diets on weight loss over a 12-month period. In addition, it evaluated whether DNA testing or insulin sensitivity measurements could effectively predict whether individuals lost weight better on low-fat or low-carb diets.

  • There was no significant difference in weight loss between the low-carb and low-fat groups at 12 months. This is consistent with multiple previous studies.
  • Both diets were equally effective at improving lipid profiles and lowering blood pressure, insulin, and blood sugar levels. This is the dirty little secret that many low-carb enthusiasts don’t tell you. The improvements seen in health parameters such as lipids, blood pressure, insulin, and blood glucose are due to the weight loss, not whether the diet is low-carb or low-fat.
  • Neither the DNA pattern or insulin sensitivity offered any predictive value as to whether a low-carb or low-fat diet was more effective for weight loss.

That means you can forget the weight loss claims of the low-carb enthusiasts. You should also ignore companies that promise they can select the best diet approach for you based on some simple DNA tests and/or measurements of insulin sensitivity.

As for what works and why, I cover that in detail in my new book “Slaying The Food Myths

 

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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Latest Article

Headache Relief By Treating Your Shoulder

Posted June 18, 2019 by Dr. Steve Chaney

A Headache Remedy Can be Treating Your Shoulder

Author: Julie Donnelly, LMT –The Pain Relief Expert

Editor: Dr. Steve Chaney

 

 

When you experience the debilitating effects of headache pain, you just want headache relief.

headache relief from painYour head throbs. It’s hard to think. It’s hard to enjoy life.

What should you do?

  • You could take Tylenol or some other drug, but that offers temporary relief at best.
  • You could see a chiropractor, but it may take multiple visits to correct your problem.
  • You could get a massage, but the headache will probably come back.

What you really want is a natural protocol you can use to make the headache go away whenever it occurs. There is such a protocol. It’s called muscular therapy, and I teach people how to perform it on themselves whenever a headache or joint pain occurs.

 

What Is The Difference Between Massage And Muscular Therapy?

There is a difference between massage and muscular therapy as a headache remedy, and both are worthwhile.  Massage is great for moving the fluids (like blood and lymph) through your body and getting muscles to relax. It’s perfect if you’re under stress and you feel like you’re going to explode.  A good massage therapist can have a positive impact on your nervous system and blood pressure, and you’ll come out walking on air.

Muscular therapy, the way I do it anyway, is more focused than it is general.  You’ve heard about spasms, but most people can’t visualize a spasm, so they ignore the term. You probably have an idea that a spasm may be painful, and it isn’t a great thing to have, but what is a spasm?

What is a Spasm

headache relief muscle knotsI explain it as a knot in the muscle.  Through some very complicated physiology (that none of us need to know about) the muscle forms a knot in the thick part of the muscle, and it’s putting a strain on the two ends.

Both ends are attached to a bone, so the pressure causes a strain on the end points and you have pain at the bone.  Most of the time the end points are just after the muscle crosses over a joint, so you end up with joint pain.

 

Too often people think this is arthritis and they are stuck suffering or taking strong drugs to mask the pain.  But in the majority of cases it’s not arthritis, it’s just tight muscles pulling on the bones of the joint and preventing them from moving freely.

But, all you need is to know where the knot (spasm) is, and then apply direct pressure on it.  Hold the pressure for 30 seconds or so, and then let go.  Keep repeating this until it doesn’t hurt anymore.

Headache Relief

headache relief shoulderLet’s say you have headache pain.  There are so many muscles that impact headaches that it would take a book (like my book: “Treat Yourself to Pain-Free Living”) to discuss each of them.  So, let’s just look at one muscle, the Levator Scapulae.

The Levator Scapulae is responsible for lifting your shoulder up.  In fact, the nickname for the Levator Scapulae is “the shrug muscle.” But look at this graphic and you’ll see where the knots form (the round red circles) and where you feel the pain (the red shaded areas).

You may not think to press on your lower neck/shoulder when you feel headache pain.  This muscle also causes the pain you feel in the middle of your back, between your shoulder blades.

 

And self-treatment is so easy!

 

headache relief shoulder muscle workYou can put your opposite thumb into the front of your shoulder as shown in this picture, and your fingers in the back of the muscle. Then squeeze your thumb and fingers so they pinch the entire muscle.

 

headache relief shoulder muscle pressure using wallOr you can put the perfect ball on the very top of your shoulder and then lean into the corner of a wall as shown in this picture.

 

What you are doing is forcing the acid (as in Lactic Acid) out of the muscle fiber so blood can fill the void and heal the muscle fiber.  As you do this you are untying the knot and the pressure is removed from the joint. In most cases the joint can now move more freely and without pain.

All the self-treatments in my book are just this easy!

Most people have significant pain relief, and I am happy to say many get total and permanent pain relief.  Try it yourself, self-treatment is easy.  The worst thing that can happen is nothing, and the best thing that can happen is regaining normalcy.

Why stay in pain when it’s so easy to find the muscular source of the problem and eliminate it?

pain free living book coverGet Treat Yourself to Pain-Free Living . It is filled with over 100 pictures and descriptions proven to show you how to find and self-treat muscle spasms from head to foot!

Join the 1000’s of people worldwide who have discovered that tight muscles were the true source of pains they thought were from arthritis, fibromyalgia, and other serious conditions.  You have nothing to lose, and everything to gain by releasing tight muscles.

Treat Yourself to Pain-Free Living is your step-by-step guide to pain relief!

 

Wishing you well,

 

Julie Donnelly

Julie Donnelly

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.

 

About The Author

Julie Donnelly is a Deep Muscle Massage Therapist with 20 years of experience specializing in the treatment of chronic joint pain and sports injuries. She has worked extensively with elite athletes and patients who have been unsuccessful at finding relief through the more conventional therapies.

She has been widely published, both on – and off – line, in magazines, newsletters, and newspapers around the country. She is also often chosen to speak at national conventions, medical schools, and health facilities nationwide.

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