After a two week vacation from this blog and my twitter account (only half of which was because I was actually on vacation!), I came back today with a guest post over at AICR. Hop over and join the conversation about what cancer screening strategies are available for prevention.
I read a great tweet last week noting that healthy foods are NOT more expensive than unhealthy foods, but they take time and practice to make tasty. It got me thinking about why, first as a struggling graduate student and, now as a working parent, I have always been committed to cooking healthy dinners.
I think a big part of it is that I grew up this way and I learned how to do it from an early age. My grandmother was a home economics teacher in a small rural town, married to a dairy farmer. Money was tight and so was time. My grandmother planned the menu for the week every week. That meant she only bought what she needed at the store and she didn’t have to figure out what to make when she got home. I remember the menu (& running grocery list of items she’d run out of) being posted on her fridge long after she’d retired and my grandfather sold his cows. When my mom and her sister got old enough (and at an age far younger than we seem to put them to the task these days), dinner preparation fell to them. They knew exactly what they needed to do, because it was all laid out for them. They’d also both grown up in the kitchen, watching and learning. I have no doubt this is why both are such great cooks now. I dare anyone to roast a more perfect turkey than my mom or make a better pecan pie than my aunt. This approach wasn’t highly unusual for my grandmother’s generation. My Dad’s mom knew what she was cooking for the week too!
Growing up, my mom did the same thing as my grandmother. That meant as a kid I remember, she too came home from a long day of work, got our whole family fed a nutritious tasty meal and then went off to graduate school classes (yes, she WAS super mom!). My mom took me grocery shopping with her. I learned how to read nutrition labels to figure our how many grams of sugar were in each and I could pick any cereal with 6 grams or less. I learned how to balance a checkbook from her after watching her write the check each week.
When I got to junior high, I took home economics and shop (though we called it something funny, like technology, though the most technologically advanced thing in the room was the VCR brought in on days when we had a substitute). We learned to read a recipe, cook and sew in home economics (things I already knew but many of my classmates did not). But menu planning wasn’t part of home ec, nor was budgeting. Nutrition was, sort-of, part of health and banking was, sort-of, part of social studies. I guess because we were all expected to go to college, we somehow didn’t need to know how to manage a household? My husband grew up halfway across the country. He had a class called “Foods” where he learned to cook, but as with me, little else of what my grandmother’s home ec taught.
Many schools have long lost home ec – it was an early victim of budget cuts (though some have retained it and modified it to meet the times in just the ways I suggest). With obesity rates among kids sky rocketing, we need to think about the critical life skills kids need to learn. Historically, home economics was exactly the transdisclipinary integrated applied course we talk about being novel in education: nutrition, economics, math, chemistry (what do you think baking is?), medicine. And if you’re lucky, you end up with apple pie. What could sound better (or more American) than that? Just don’t cut PE to pay for it.
Today marks the start of National Women’s Health Week – a fantastic initiative that brings together all kinds of different groups around important issues for women, like physical activity and self-care! I have the huge honor of guest blogging about women’s cancers over at the American Institute for Cancer Research (AICR) blog today. AICR is the amazing group behind the reports on nutrition, physical activity and obesity and cancer. The report, which undergoes continuous updating as new science emerges, is an incredibly comprehensive expert review of the science around food, exercise, weight and cancer.
Check it out the blog and the report!
In prevention, I’ve noticed something pretty predictable happens when a new study comes out noting the health harms of certain lifestyle factors (alcohol, obesity, and red meat intake are particularly prone to this) – the internet lights up with someone posting (and plenty of others linking) about why we can’t trust anything that comes out of observational studies.
I am not going to sit here and pretend that there aren’t limitations to observational studies – there are and I know them well – that’s what the foundation courses in epidemiology teach you – the limits of each study design.
But let’s be perfectly clear about something else, randomized trials aren’t perfect either. They aren’t perfect when perfectly conducted and almost none are perfectly conducted. They can’t be. Randomized trials are done on people, who are imperfect. So that means people don’t comply with randomization and they quit the study.
This isn’t news. If we thought the (THE) randomized trial was perfect, we’d only do one. So we wouldn’t have need for meta-analyses of randomized trials, which proliferate in the literature.
Randomized trials are subject to interpretation. One need only to compare how the same set of studies can be interpreted quite differently by the thoracic surgeons and gastroenterologists when each group issues treatment guidelines.
Does this mean randomized trials are no good? Absolutely not! In fact I recently wrote a paper with my colleague Graham Colditz about the importance of intervention trials specifically in cancer survivors, though we also noted the limits to what such trials can show.
We need to remember that we can’t (and never will) base all of our health and medical decision making on trial data. I will continue to trust in the value of parachutes, despite the alarming findings of this analysis of trial data from the esteemed British Medical Journal.
My colleagues at Cancer News In Context & Washington University School of Medicine have put together a nice graphic on the pros and cons of observational versus randomized trial data. I think it is a nice summary of how BOTH study designs add value to our understanding of health. Which one is “best” is VERY dependent on the specific question of interest!
Last night I attended a special screening of HBO’s The Weight of the Nation. The event, co-hosted by the Consortium to Lower Obesity in Chicago Children (CLOCC), the Chicago Department of Public Health and Comcast demonstrated one of the key points in our Advancing Cancer Prevetnion paper – tackling these large problems is going to require us to come together across traditional disciplinary boundaries. That doesn’t mean a geneticist and clinical psychologist collaborating. It means media and science and policy and advocacy all in the same room saying, “ENOUGH.”
I saw a post on Twitter recently from Jody (@jodyms), who was so excited to be able to participate in a cancer research trial. And I was thrilled to see it. There is a lot of bad information out there about research. And, yes, there is still too much weak scientific research going on and we haven’t fully accounted for the unethical research practices of our past. But here’s why we shouldn’t throw the baby out with the bath water.
There is lots of research out there that can help you.
I’m going to do something that may not be really popular, or good for my career, but let me explain how I’d talk to my mom and her friends about participating in research. Let’s say one of the ladies in my mom’s yoga group, Barb, was approached about participating in a 6 month weight loss trial. Women of her age and menopausal status are a popular demographic for these kinds of studies that promise 10% body weight loss (or more) in a fairly short time with an intense tightly controlled dietary regimen. They’ll measure all kinds of physiologic changes. And this kind of science is valuable – it might provide clues to what happens in the body when weight changes – helping us better understand why weight changes lead to disease risk changes. Or, as I’ve seen in plenty of grant applications, identify the physiologic or molecular target that we can put a drug on to get the benefit of weight loss for health, without the work of losing weight. We need people who will participate in trials like these – they are important for advancing science. But is there a real benefit for Barb? Honestly, maybe not much. The study isn’t interested in helping Barb make better, healthier, choices. They aren’t including the behavioral strategies she needs to achieve long term weight loss. That’s not their goal. (Harsh? yes. True? pretty much.) So when the study is over, Barb will go back to living her life and the weight will likely come back. (You can say maybe not, but I can pull a pile of studies that show this is what happens – achieving short term weight loss is relatively easy in science, keeping it off is not. Most people gain the weight back, and then some – so they are worse off.) And it turns out, weight cycling is actually not good for your health. Maybe participating in that study does more harm than good for Barb.
But what if Barb was approached about participating in a weight maintenance study? Honestly, it would probably sound a whole lot less appealing to Barb, who’d like to lose a little weight. But the weight maintenance study is focused on helping Barb make long term changes in her life. Those that are durable. Durability is what matters for your risk of heart disease, diabetes and cancer. Is Barb going to see a benefit from participating in this study? Yup. Because even if she doesn’t lose any weight, if she doesn’t gain any weight, she’s better off. The reality is there all kinds of in between and Barb needs to know what she’s getting and what she’s not getting.
I’m not saying people shouldn’t participate in trials that provide them with no direct personal benefit. The generous men and women who have knowingly volunteered to do so have advanced science in countless, critical ways. My lab does BOTH kinds of studies. We ask people to complete surveys during their cancer care that will provide us with important information to identify intervention targets and it won’t directly benefit the men and women who complete those surveys. But there is also science out there that can benefit the participants, directly, and we do this science too. If you aren’t willing to do the former, you might be willing to do the later. If you’re asked to participate in a research study, ask the questions and find out more before you say no. It might be a study that helps us advance science or it might be one that helps you AND advances science.
The American Cancer Society recently released a revision to their nutrition and physical activity guidelines for cancer survivors. The guidelines were compiled by an expert panel that reviewed the wealth of new evidence that has been published since the original guidelines were released in 2006. While many of the guidelines are similar to those for cancer prevention, the proliferation of high quality science in the subsequent years has led to some key refinements in the messages.
Here are a few highlights:
- When it comes to question of nutrition and physical activity, “survivors soon find there are few clear answers to even the simplest questions.” What the evidence base shows is that the answers on what foods or what exercise will likely vary , in some regards, from one cancer to another (remember, we say “cancer,” but we’re talking about dozens of diseases) and based on treatment type as well as numerous other individual level factors. Despite this and that more research needs to be done to fill in the gaps (e.g., more than 80% of the intervention evidence for the safety and efficacy of exercise in survivors comes from breast cancer populations), recommendations on exercise and diet can and have been made.
- The ACS guidelines are for primarily targeted to health care providers. (Exercise professionals looking for field specific guidance can turn to the ACSM guidelines.) Why target providers? “Physicians and other health care providers have a unique opportunity to guide cancer patients toward optimal lifestyle choices, and thus can favorably influence the survivorship trajectory regardless of the individual’s survivorship phase. The power of physician advice in facilitating preventive health behaviors has been consistently demonstrated.” Patients look to providers for information. Unfortunately, physicians aren’t always well informed about the evidence for the importance of lifestyle. (Many are, but it is more common for me to meet an oncologist surprised at the depth of evidence for the benefits of exercise among survivors than to meet one who is well versed in it.) These guidelines are an important part of that education and outreach process. Physicians need not do all the counseling themselves, but do need to provide referrals to the appropriate followup lifestyle care such as with a certified fitness professional or nutritionist.
-Addressed with new gusto in the ACS guidelines is supplement use, with good reason. “A recent systematic review indicates that 14% to 32% of cancer survivors initiate supplement use after their diagnosis. Breast cancer survivors report the highest prevalence of supplement use, whereas prostate cancer survivors report the lowest.” Despite the high prevalence of use, the guidelines note, “dietary supplements are unlikely to improve prognosis or overall survival after the diagnosis of cancer, and may actually increase mortality.” The appeal of supplements is logical – people often feel they are struggling to get adequate nutrients through foods, and a whole industry exists to play to that concern. But the guidelines are clear: “Before supplements are prescribed or taken, all attempts should be made to obtain needed nutrients through dietary sources. Supplements should be considered only if a nutrient deficiency is either biochemically (eg, low plasma vitamin D levels, B12 deficiency) or clinically (eg, low bone density) demonstrated. Supplements should be considered if nutrient intakes fall persistently below two-thirds of the recommended intake levels. Such a determination should be made by a registered dietitian.”
The supplements provide a nice example of why patient provider communication is key to healthy survivorship. If providers don’t know what patients are doing, eating, taking, they can’t provide the recommendations of what to continue and what to change. As the guidelines note, “Open dialogue between patients and health care providers should occur regarding dietary supplementation to ensure there is no contraindication in relation to the prescribed cancer therapy or for longer term health effects.” In fact, open dialog is important for making any lifestyle change!