Student Blogger

By Allison Dostal, PhD, RD

Dept. of Medicine, University of Minnesota Medical Center, Division of Gastroenterology, Hepatology, and Nutrition

ASN’s immediate Past President Patrick J. Stover, PhD, has been elected as a new member of the National Academy of Sciences (NAS) in recognition of his achievements for original science and research in nutrition. In addition to his important work with ASN and the NAS, he directs Cornell University’s Division of Nutritional Sciences and maintains an active research program. Through all of these accomplishments, Dr. Stover hasn’t lost sight of the many pitfalls, challenges, and chance happenings that have led him to the successful career he has today. In this interview, Dr. Stover discusses his trajectory from graduate student to ASN’s 2015-2016 president and NAS member and offers valuable insights that both young and established scientists can take to heart.

“Relationships are so important in science. They’re absolutely critical.”

Planning a career after completion of a PhD takes considerable, thought, effort, and not a small amount of stress. And yet, there’s no denying the power of chance and serendipity. For Dr. Stover, attendance of a summer conference in Vermont just one week before defending his dissertation forever changed his career focus. “They had messed up room assignments – I was supposed to room with my PhD advisor, and instead I ended up rooming with chair of nutrition at Berkeley, Barry Shane. My intention was to do a postdoc in crystallography and catalytic antibodies, because my PhD is in biochemistry. But I got that room assignment, and Barry and I just got along so well that week. I kept trying to find my thesis to do my thesis corrections, but he kept taking it with him because he wanted to read it. I changed my postdoc plans and went to Berkeley in nutrition. That’s really how I got introduced to nutrition – through that gratuitous error in roommate assignments.”

When asked what he believed his greatest career accomplishment to be, Dr. Stover immediately responded, “Oh, that’s easy. The greatest accomplishment is finding and working with some absolutely wonderful collaborators and mentors. This also includes students. The successes have always been finding the right people to work with that enable you to address the important questions, of both scientific importance but also public health importance.”

Stover was trained as a metabolic biochemist when he first started his faculty position, with an interest in folate metabolism. He soon realized that the most important questions that matched his interests were related to fundamental mechanisms of the role of folate in birth defect prevention. “We knew it worked; we didn’t know why it worked. And going out and finding people who were experts in embryonic development or an expert in cancer, and being able to work with…people who were experts in these other areas who didn’t know about or weren’t familiar with the science that I knew, [we were able to] put those two together and solve interesting problems and learn new techniques.”

“All good research starts with an interesting, important question.”

This concept is “absolutely paramount” for young scientists to understand as they enter a research career, Stover says. Along with this, “You really have to love what you do. You have to love asking these questions and love doing research.” After having this foundation and investment in the work of discovery, the next step is ensuring that one has the proper training, tools, and collaborators to be able to address the important question at hand.

“You have to collaborate. You don’t have to know everything, but you have to know what you don’t know and who you need to work with to be successful.”

Dr. Stover acknowledged that today, a lot of the important questions that many of us are interested in require multidisciplinary approaches and collaborative work, because these problems require different perspectives, tools, and techniques.

He also mentioned that throughout the years, ASN’s Graduate Nutrition Education Committee had written pieces about the importance of being an expert in something, but also having a broad knowledge base. “You have to be deep in what your expertise is – your disciplinary expertise and your technical expertise. But that’s not enough to address many of the important public health problems and the important scientific questions we have.”

Dr. Stover also recognized the increasing importance of communicating our science to other researchers and the general public. “A lot of us increasingly have to be well aware that what we’re interested in, and what excites us, has to be effectively communicated to external audiences so that they’re excited to support our work, [and to] the federal government so they’re excited to fund our work”.

Many of the issues Stover has had to navigate as a scientist are not unlike those that concern young investigators today. When discussing the biggest challenge that he’s had to face in his career, he emphasized the difficult transition from focused researcher to faculty member. “As academic faculty…we get our positions because we’ve been good at research. And then we get these faculty positions and we get put in offices, and we get asked to teach, and we get asked to manage personnel, and get asked to manage budgets and do some administration, for which we are utterly unqualified and untrained for, for the most part. I think being an assistant professor is really, really tough.” He noted vast improvements in career training tools since he first became an assistant professor in 1994, highlighting ASN’s workshops on effective teaching, mentoring, and skill sets needed for professional development.

As he continues to amass accolades and respect for his scientific career, Dr. Stover shows no sign of slowing down. When asked about the nutrition science-related goals he would like to achieve, he offered insight for both his own research program and for ASN. “In my own work, we continue to be really interested in the molecular basis of pathology related to folate metabolism, because we’re very interested in how folate requirements differ among individuals and how those affect important endpoints like genome stability and gene expression.” He also spoke about improving nutritional approaches to address diseases such as neuropathy, cancers, and neural tube defects, all of which are tied into folate’s role in human health. “We want to provide an engineering approach to understand how these things work and how nutrition throughout the life cycle can be used to improve the quality of life and wellness of life.”

He also intends on having a broader impact. Stover acknowledged that the number of ASN members elected into the National Academy of Sciences is very small, despite the excellent work produced by nutrition researchers that belong to ASN. “We need to get more outstanding nutrition scientists into greater visibility. I want to really work for that as well.

This interview has been condensed and edited.

By Chris Radlicz

This past October, the International Agency for Research on Cancer (IARC), the cancer agency of the World Health Organization (WHO), made headlines when they classified processed meat as a Group 1 carcinogen. This classification was based on “sufficient evidence in humans that the consumption of processed meats causes colorectal cancer”. Additionally, red meat has been classified as a Group 2A carcinogen due to “limited evidence that consumption of red meat causes cancer in humans and strong mechanistic evidence supporting a carcinogenic effect” [1]. These IARC statements advocating a limited intake of processed and red meats tend to be misconstrued by the public and many may take it to mean that all meat should be avoided. Besides the inherent benefits of protein and various micronutrients in meat, red meat is primarily trumpeted as the best source of heme-iron in the diet. With iron deficiency as the most common nutritional disorder in the world [2], limiting red meat may not be prudent advice. What, therefore, is unique to red meat and processed meats which explains their carcinogenic potential?

What gives meat a bad rap is not inherent in the animal muscle itself, but rather the preservatives added to meats and the cooking processes which meats undergo. So what can be done to mitigate and avoid the proposed cancerous effects of some meats? Below are some practical tips to be conscious of and implement when meat shopping and preparing meats so that consumers can take full advantage of the nourishment from meats while limiting any risk

  • 1. Cook with Moist Heat: The Journal of the American Dietetic Association in a 2010 article, showed that cooking with dry heat promoted a 10 to 100-fold increase in advanced glycation end products (AGEs). AGEs increase oxidative stress and inflammation, and have shown to be a player in the pathogenesis of many chronic diseases. Cooking with moist heat, at low temperatures, and shorter cooking times have all been shown to reduce AGE formation [3]. Cooking meat in stews and sauces at low temperatures for longer periods of time, typical of crock-pot style cooking, is an effective way to reduce formation of these questionable AGEs.
  • 2. Avoid Charring Meats: Cooking meat at high temperatures, typically on a grill or skillet, can lead to browning or charring. This browning is known to occur as a result of the Maillard reaction which has been shown to produce heterocyclic amines (HCAs), and polycyclic aromatic hydrocarbons (PAHs). PAHs form when fat from grilled meat is ignited, causing flames containing these PAHs, which can then adhere to the meat’s surface. HCAs are formed from amino acids, sugars, and creatine reacting at high temperatures. These chemicals have been shown to be mutagenic to DNA after consumption and digestion, leading to genetic instability and increased risk of cancer [4]. Cooking meats at higher temperatures and for long periods of time will lead to increased HCAs, while smoking and charring will result in more PAH formation. No Federal guidelines exist addressing PAH and HCA consumption, but these chemicals provide a mechanism as to meats carcinogenic capacity. With this in mind, the National Cancer Institute suggests that concerned individuals should turn meat over frequently when cooking, use a microwave first to shorten high temperature cooking time, remove charred portions of meat, and refrain from using gravy made from meat drippings as ways to reduce PAH and HCA exposure [5].
  • 3. Purchase Nitrate-Free and Uncured Meats: Nitrates and nitrites added as preservatives to meat have been shown to convert to activated N-nitroso compounds (nitrosamines and nitrosamides) in the gut, and are proposed to be carcinogenic due to their ability to cause DNA damage [6]. N-nitroso compound formation can also be increased with the intake of red meat, principally due to interactions with the heme-iron [7].
  • 4. Purchase Meat that isn’t Smoked: Smoked meats fall under the category of processed meats. Epidemiological studies, have shown a correlation between cancer of the intestinal tract and the frequency of dietary intake of smoked foods [8]. More convincingly, the smoking process forms N-nitroso compounds and inevitably contain high levels of PHAs.
  • 5. Purchase Antibiotic-Free Meat– Some antibiotics and pesticides in meats can react with nitrite to form nitrosamines in high quantities [9]. Additionally, there is much worry that the antibiotic use in agriculture is contributing to the growing prevalence of antibiotic resistance, and in a more minor capacity, to the obesity epidemic [10,11]

Bibliography

[1]       WHO | Q&A on the carcinogenicity of the consumption of red meat and processed meat

[2]       Liu K, Kaffes AJ. Iron deficiency anaemia: a review of diagnosis, investigation and management. Eur J Gastroenterol Hepatol 2012;24:109–16. doi:10.1097/MEG.0b013e32834f3140.

[3]       Uribarri J, Woodruff S, Goodman S, Cai W, Chen X, Pyzik R, et al. Advanced glycation end products in foods and a practical guide to their reduction in the diet. J Am Diet Assoc 2010;110:911–6.e12. doi:10.1016/j.jada.2010.03.018.

[4]       Cross AJ, Sinha R. Meat-related mutagens/carcinogens in the etiology of colorectal cancer. Environ Mol Mutagen 2004;44:44–55. doi:10.1002/em.20030.

[5]       Knize MG, Felton JS. Formation and human risk of carcinogenic heterocyclic amines formed from natural precursors in meat. Nutr Rev 2005;63:158–65.

[6]       You C, Wang J, Dai X, Wang Y. Transcriptional inhibition and mutagenesis induced by N-nitroso compound-derived carboxymethylated thymidine adducts in DNA. Nucleic Acids Res 2015;43:1012–8. doi:10.1093/nar/gku1391.

[7]       Rohrmann S, Linseisen J. Processed meat: the real villain? Proc Nutr Soc 2015:1–9. doi:10.1017/S0029665115004255.

[8]       Fritz W, Soós K. Smoked food and cancer. Bibl Nutr Dieta 1980:57–64.

[9]       Elespuru RK, Lijinsky W. The formation of carcinogenic nitroso compounds from nitrite and some types of agricultural chemicals. Food Cosmet Toxicol 1973;11:807–17.

[10]     Cox LM, Blaser MJ. Antibiotics in early life and obesity. Nat Rev Endocrinol 2015;11:182–90. doi:10.1038/nrendo.2014.210.

[11]     Chang Q, Wang W, Regev-Yochay G, Lipsitch M, Hanage WP. Antibiotics in agriculture and the risk to human health: how worried should we be? Evol Appl 2015;8:240–7. doi:10.1111/eva.12185.

By: R. Alex Coots
For scientists, the benefits of nutrition and health research are immediately apparent. It’s easy for us to see how the general public and policymakers alike can benefit from a better understanding of health and nutrition. Few of us would argue that we need less health research or fewer grants, but this is exactly what’s been happening since the NIH budget doubling ended over a decade ago. Decreasing budgets means fewer studies, and fewer studies means less progress on today’s pressing health problems. To help address this problem, I spent a day on Capitol Hill with professors, patients, and other stakeholders to advocate for a more sustainable and predictable funding schedule for health research.
Given the abundance of high quality research institutions in New York, I thought it would be easy to get legislators to support science. How wrong I would be. At best, congressional staff received us with apathy and at worst, hostility. During one particular meeting, an elected representative went so far as to say “All you people want is more and more and more rather than try to make what you have go farther.” And this was said by someone who co-sponsored the 21st Century Cures Act!
What became clear to me during the meetings was that the science profession was not viewed as one that provides answers to today’s most pressing questions; rather, it was viewed as just another (expensive) special interest group. While many scientists do advocate for use of scientific information in the formation of policy, not many of us advocate for the resources we need to carry out our work. Professor Lawrence Goldstein at UCSD has previously advocated for a phone call with each grant written and each grant reviewed. I’d extend this model to include a call with each paper published so that policymakers can hear the scientific progress being made in their district or state. Ensuring that scientific information is used in policy formation is only part of the advocacy battle. We scientists must ensure that our discoveries are limited by our imaginations, not by a lack of grants.