Richard S. Isaacson, M.D., serves as Director of the Alzheimer’s Prevention Clinic, Weill Cornell Memory Disorders Program, and Director of the Neurology Residency Training Program at Weill Cornell Medicine/NewYork-Presbyterian Hospital.
Dr. Isaacson specializes in Alzheimer’s disease (AD) risk reduction and treatment, mild cognitive impairment due to AD and pre-clinical AD. His research focuses on nutrition and the implementation of dietary and lifestyle interventions for AD management.
This is part two of three of our interview with Dr. Richard Isaacson.
Click here to read part one.
Jed Levine (JL): I know that people with diabetes are at greater risk for developing Alzheimer's, and there's been a lot of study about insulin resistance. What is insulin resistance and what can you do to control that?
Dr. Richard Isaacson (RI): While I am a neurologist by trade, I often feel like I am also one-third cardiologist and one-third diabetes doctor.
Insulin resistance is where the body becomes less sensitized to the effects of insulin, which is produced by the pancreas when someone needs any sort of sugar or carbohydrate. All carbohydrates break down into sugars, but there are good and bad carbohydrates. Certain carbohydrates, like plain sugar, baked goods, high fructose corn syrup, cakes, and candies will cause the pancreas to secrete insulin. Insulin is the hormone that breaks it down. If you eat too much of these carbohydrates or your pancreas isn't working, you will have greater risk for the negative effects of diabetes.
While insulin resistance can be caused by dietary and genetic factors, we are finding additional, more confusing reasons for insulin resistance. Someone can look perfectly healthy on the outside, but when we look closer we find that they have a high amount of fat on the inside, where we can’t see it. This is called visceral fat.
Insulin resistance can come from any metabolic problem in the body. It can be worsened or caused by diet and by genes. The key here is it's always an interplay between genetics and the environment. Insulin resistance is among the most modifiable pathways for a lifestyle or dietary change to push someone off the road to Alzheimer's disease.
My philosophy is, and I'm in the minority since less than five percent of Alzheimer’s specialists believe this, that while amyloid and tau are bad, if we can intervene before amyloid gets on the metabolic pathway, we can change the outcome. Since insulin resistance is one of the key precursors to amyloid deposition, if we are proactive, we can change the course of the development of Alzheimer's disease.
We take a very deep dive (some would say too deep). What we're realizing is there's a core of five to eight habits that we can change if a person is insulin resistant. We look at blood sugar level, fasting blood sugar level, and fasting insulin level. We also look at the hemoglobin A1c, which is checked for anyone with diabetes. We determine if any of these are higher than they could be or should be.
If any of these are borderline, it may not be pre-diabetes, but it may mean pre-pre-diabetes, which is worrisome for someone at risk for Alzheimer's. We take a long-term, preventative approach, literally a decade or even up to three decades before the onset is likely. Before we put someone on a personalized intervention plan, we try to understand why they're insulin resistant.
Half my patients just change their diets and their insulin resistance goes away. For the other half, the beta cells in their pancreas aren't working right. We have markers for that. For some, their body fat is increasing. This is common, probably a third of my patients seem pretty healthy but haven't been exercising as much as they had in the past, so their muscle mass is decreasing and body fat is increasing. This is normal as we age, but the question we ask is, "Is there is something we can do about it?" We fight insulin resistance from every angle, but we first try to figure out if the person has it rather than just say, “Oh, you need to eat less carbs.” Some people may eat all the right carbs and still have a problem.
There's actually a fascinating Alzheimer’s prevention study going on right now called the Tomorrow Study. Doctors are using a diabetes drug called pioglitazone, which is an insulin sensitizing agent, to figure out who can benefit from the drug.
JL: There are so many dietary things that we hear about in terms of coffee, red wine, antioxidants, blueberries, etc., but changing diets is very difficult. If you look at this as a public health issue, once you get data, will you have recommendations? How will you get the message across? We know it takes a long time to change behavior.
RI: There's two parts to your question. First, there's no one-size-fits-all approach to Alzheimer’s risk reduction, Alzheimer's treatment, or overall brain health. There is a brain-healthy diet, but different people need different brain-healthy foods depending on their metabolic and nutritional status.
The second is determining the best way to communicate to affect behavior change. For people who have insurance, we can send them to our nutritionist, who puts a very detailed plan together. For others, we have online material. There is a two-page summary of good vs. bad carbs and a top ten list of what you need to eat. Does this really help? Maybe a little bit.
There are two things that have helped the most. First is online education, where people can go on their computers and watch interactive modules about nutrition and find explanations about what a carbohydrate is, what fiber is. People don't understand that while fiber is a carb, it's actually not digested, so it doesn’t really count as a carb. And with online education, people can learn in the comfort of their own home.
The other thing that's affected change most is asking our patients to track the food they eat. It's difficult to get the patients to track, but once they do it, it works. We ask them to track at least three days in a week every six months. This really works.
When I tried it myself, I was surprised. I thought I was eating very healthy food, but when I tracked it, I found that I had eaten 226 grams of carbohydrates in one day! The RDA is 130. I'm supposed to know this, right? The problem is that even highly motivated patients have a tough time tracking data consistently.
JL: When I track everything I eat or even just count carbs, either on Weight Watchers or MyFitnessPal, it's the only
way I lose weight. But it’s demanding.
RI: It took me 35 minutes, so we developed tips and tricks for both online and paper tracking. People don't have 35 minutes. If they do, they should be exercising for those 35 minutes.
We tell people to track their weight and their percent body fat, and to get a scale. I check the Health app on my iPhone because I want my 10,000 steps every day, even if I've had a busy, terrible day. Last night I was at 9,485 steps, and I walked the dog one extra time at 11:00 because I have to achieve those 10,000 steps.
There is some data to suggest that if you weigh yourself more than 15 times a week, you lose more weight. I check my body fat every month on a percent body fat scale. We teach our patients to do these things. If people don't have any time, we teach them ways to incorporate the time.
For example, we have a balance ball in the office. I sit on it one to two hours a day, because sitting in a chair for eight hours a day causes my metabolism to plummet. A balance ball will actually activate the core. I might get a standup desk. Whatever little tips and tricks you can do to help. With diet, you have to make your brain and belly happy. With lifestyle, you have to stay in balance with kids and school and this and that. It's hard.
JL: There is also the difficulty of delivering the message that there is a difference between maintaining cognitive health and preventing diseases like Alzheimer's or other cognitively impairing illnesses.
RI: In our Alzheimer's Prevention Clinic, which provides direct clinical care to people at risk for Alzheimer's before they have symptoms, we try to apply the best evidence we have towards reducing risk and maintaining cognitive health. The problem is that so many of these studies use cognitive health, or Alzheimer's prevention, but do they really look at Alzheimer's? Do they use biomarkers? Was it dementia prevention? Was it cognitive health prevention? The data is so muddy. It’s really tough to tease out.
To know if we're truly preventing Alzheimer's, it's going to take time. We finally have funding to study Alzheimer's biomarkers. We can look at amyloid and glucose metabolism in the brain. The Holy Grail here is not just showing that we're improving cognitive health, because we've shown this with the FINGER study, which was the first multi-domain intervention that showed that lifestyle change, plus nutrition, exercise, socialization and regular healthcare follow-up can delay cognitive decline in an elderly cohort. It was a well-done, landmark study. We practice that clinically today, but we also add clinical precision by looking at genetics and stratifying based on genes, looking at biomarkers and taking a personalized approach.
Will this impact glucose hypometabolism or amyloid deposition? That's what we need to prove. We began a new study in January. So yes, we are looking at this, but, it's going to take at least five to ten years to truly know if this approach affects Alzheimer's onset or not. Right now, we don't have enough information.
Read the final part of the interview in the winter 2017 newsletter.