Kevin Klatt, PhD, RD

I had a soon-to-be-RD friend of mine ask me to write up a brief article on how clinicians can respond to clients who would like to go, or are, Paleo. 1. No diet is perfect by name - it's all about the nutrients you intake. Most dietary mantras (Mediterranean, Veg*n, Paleo, etc) can be healthful assuming you get adequate amounts of all your nutrients, but many have their drawbacks - Paleo is no exception. When it comes to Paleo, there's a few nutrients to keep in mind: Iodine: eschewing dairy and choosing sea salt can potentially cut large sources of iodine in the diet. Advise individuals to consume seaweed, incorporate some iodized salt, or take a Kelp extract supplement (be careful not to overdue with the supplements if it gets to that point, many contain 2-3x the RDA).  Manganese: It's not a mineral we hear talked about a lot, but the major sources of it are grains, especially brown rice. If the individual is just concerned about gluten, brown rice can be a great op...

If you didn't hear, there was a pretty controversial report in the Annals of Medicine put out claiming that consumers should stop wasting their money on Multivitamins (1). In my opinon, a more appropriate summary is to not expect anything that great from popping your daily. I've got a lot of thoughts on this issue so let's break it down: 1.  May the Odds be Ever in your Favor - tossing a bunch of vitamins and minerals into the intestines at once is a bit like the Hunger Games- you've got a bunch of competitors, some will beat out others (for absorption) and maybe one will win out (be highly bioavailable) at the end. if you've ever taken a course on micronutrient metabolism, you'll probably hear this report and think ..'duh?' Mineral bioavailability is dependent upon a number of factors, and is largely inhibited by the presence of other minerals. Think back to your high school chemistry days - what happens when you put a bunch of positive charged min...

As I've written before on my posts at the-sage.org, I'm not against the paleo diet - it's backed by a really shallow understanding of evolutionary theory and desperately needs a name change (Unprocessed/antigrain isn't very sexy, I guess), but overall, I don't see a huge worry for nutritional deficiencies - depending on the strictness/vigilance, an individual might be low in calcium, iodine, manganese and vitamin E. From a clinical perspective, I'm more concerned with those consuming standard American diets. From a scientific perspective, I'm mostly concerned with religious evangelization of a dietary mantra posing as science. I had a friend send me this link , claiming that gluten free diets are backed by 'real' science and asked me for my thoughts. For one, i'm familiar with Robb Wolfe, and generally like his and Matt LaLonde's call for a harder science approach to the Paleo movement. I am a big critic of the dietetics education standards...

I just got back from the American Society for Nutrition's Advances and Controversies in Clinical Nutrition conference and came back with a lot of ideas for blogging.  I was happy to see a number of things i've blogged about and my thoughts on clinical nutrition were covered at the conference, with similar conclusions - I identify more as a scientist and less as a future clinician so it's good to see i'm not totally off base with reality. One very interesting talk was given by the chair of the Food and Nutrition Board (FNB) of the Institute of Medicine (IoM). Before I go on to discuss some relevant points from her talk, there's a few definition you'll need to be sure of (1): Dietary Reference Intake (DRI's ): reference values that are quantitative estimates of nutrient intakes to be used for planning and assessing diets for healthy people (Recommended intakes and Upper Limits) Recommended Dietary Allowance (RDA) (newly called AMDR): the average daily ...

Credit: Hindawi.com               When it comes to Omega 3's, form and source are quite important, both from a health and evolutionary perspective. There are three kinds of these fatty acids: alpha linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). ALA is the shorter plant form, and currently the only form considered essential; ALA can be elongated into the longer chain EPA/DHA, found in fish and phytoplankton, via fatty acid desaturases (enzymes your liver produces).               Referring to ALA as the only essential omega 3 fatty acid has been an issue of contention in the field of nutritional sciences. EPA/DHA, at low doses, are thought to be potent anti-inflammatory agents, lower triglycerides , and help maintain cholesterol homeostasis, via decreasing lipogenic gene expression in the liver (2), all having prof...

Pigmentation is a great model for teaching evolution and demonstrating the concept of a polygenic trait - there are a number of alleles at different loci at variable frequencies throughout the population.  This variability has been disproportionately seen across a latitudinal cline, with darker skin tones being present around equatorial regions, and a lightening seen as latitude increases. An estimated 88% of total pigmentation variation in humans can be explained by geographic differences; for reference, geography can only explain 13% of craniometric variation, another highly quantitative trait. Considering the recent evolution of modern humans, this drastic geographic distribution in pigmentation has been thought to be the result of strong selective pressures. The major differences in pigmentation are due to the amount and type of melanin synthesized in the melanocytes, and the shape and distribution of the melanosomes, organelles that transport and store melanin . Melanins are...

I'm all for sustainability - I actually ran a Sustainability Living Community in my undergraduate and was involved with a number of sustainability-related groups. The intersect between the food system, nutrition, and the environment has always interested me, and the vast array of opinions on the topic always gets a nice scientific debate going. That being said, there are some efforts that aren't always the best for you. I was at Whole Foods today and saw milk being sold in glass bottles, advertised that it came from a small farm with a nice picture of a happy cow on the front. After having just gone through Vitamins week in the class I teach, photolysis was on my mind. Milk is the highest source of riboflavin for those consuming a typical Western diet. However, riboflavin in milk is particularly susceptible to photolysis - light degrades the biochemical structure of riboflavin (1). Those glass bottles that milk is being sold in may be re-usable and considered better for the...

I really applaud anyone who is trying to make positive changes to their lifestyle, especially by improving their nutrition but, few things annoy me more than massively disseminated misinformation. The most virulent case of this is linoleic acid, an omega 6 (n-6) fatty acid. Do one google search of "Omega 6's and Inflammation" and you'll find articles on every internet health site, written by MDs/RDs/etc etc, telling you that Omega 6's, like those found in vegetable oils, are virtually the cause of every modern day ailment, from heart disease, to acne and arthritis. They'll cite you information stating that the n-6:n-3 fatty acid ratio is all out of whack. There seem to be 2 reasons that people claim linoleic acid is pro-inflammatory. 1, because it is a precursor to inflammatory molecules in the body. 2, because it is subject to oxidation, and these oxidative endproducts (reactive carbonyl compounds, ketones, aldehydes) incite an immune response . 1. Lino...

One of the most common 'anti-nutrients'/organic compounds that alternative health/ancestral diet followers seem to talk about is phytic acid. The structure of phytic acid contains an inositol group (similar to B-vitamin structures) and 6 phosphate groups. Phytic acid exists in plant foods, particularly high in nuts, seeds, whole grains and legumes. Phytic acid is a particularly important reservoir of phosphorous and other mineral cations for a plant - plants contain the enzyme phytase, which can hydrolyze the bonds between phytic acid and its bound minerals (phytic acid:mineral complexes are known as phytates). Humans do not produce phytase, though some bacteria in the human small intestine may have phytase activity, allowing for the release of a small fraction of the bound mineral. The human GI tract's pH, also, does not facilitate the liberation of minerals from their phytate complexes. Phytic acid most commonly binds to non-heme iron, zinc, and calcium (1). From an evo...

A study came out in Gastroenterology (1), that I find to be nicely timed with my most recent post on the need for controlled studies surrounding issues like gluten. I am in no way saying this is the be all end all for the gluten-free fad, but this is a scientific step in the right direction for understanding the role of gluten, if any, in medical conditions. A lot of people are avoiding gluten for a number of reasons - they think it causes weight gain, it's 'toxic', causes GI discomfort, skin problems, etc etc. Much of the information that pushes gluten-free diets is anecdotal, and doesn't control for confounding factors - when it comes to food, there are hundreds of food components/chemicals to consider, at both the macro and micronutrient levels, as well as the many interactions between said components. I must admit a pretty non-scientific sentiment- I've always been a bit skeptical of the scientific community's acceptance of gluten sensitivity. Not that ...

Registered Dietitians get attacked by a lot of sub-groups in nutrition for not being one of a myriad of things, depending upon the dietary mantra of the group - low carb'ers accuse RDs of heresy for recommendations concerning the consumption of carbohydrates and allotting for some level of added sugars in the diet; paleo'ers attack RDs because they push whole grains and dairy, purporting that these are two of the major toxins in our food supply; vegetarians/vegans say that RDs are pushing cancer-causing animal products that harm the environment and cause unnecessary suffering. These are just a few of the major nutrition-minded groups that have asserted their dominant, superior nutrition viewpoint and attacked the current medical model of nutrition. But who is correct? Put any of these 3 major groups alone in a room together and everyone may very well not make it out alive, or at least without being covered in Red paint and/or being accused of ignoring your primal blueprint. ...

If you're reading this expecting me to either endorse or stand in opposition to high-protein diets, turn back now. In nutrition, it's difficult to make a simplistic recommendation out of the mounds of scientific literature that exists on a topic - I can't imagine the stress that the Food and Nutrition Board of the Institute of Medicine (IOM) is under while making population-level recommendations. Protein is probably the most well studied of the macronutrients, from a physiological and biochemical perspective - the worldwide obsession with ensuring adequate 'complete' protein intake enveloped a lot nutritional sciences research in the 1900's. From this research, we learned a lot about amino acid metabolism/catabolism and understand the basic needs of most humans. It's known now that it's not necessary to only eat complete proteins, and that eating a combination of plant foods can provide all of the amino acids - hence, vegetarians not completely wasting...

I've mentioned before that, if one is trying to emulate a past hominid's diet in an attempt to have a more 'ancestrally-aligned' pattern of eating, it is rather difficult to accurately do this because it is rather difficult to discern what our ancestors actually ate (among a host of other reasons: plant domestication, methods of processing, which hominid, etc etc). Researchers in this field are able to chemically analyze calcified plaques from fossilized neanderthal teeth. There are a couple issues with this - most notably - the last meal effect: just because you find these remnants doesn't necessarily mean that individuals were eating these foods regularly. It would require a large cohort of fossilized teeth from diverse regions to make a more robust statement that Neanderthals regularly consumed these food products. Past assumptions were that Neanderthals were overwhelmingly carnivorous and rarely consumed plants foods; recently, analyses of tooth plaque have ...

That title is half a fiber joke and half pointing to the need for a Nutrition Fact Check website (similar to the politics version ). Fiber also happens to be a great way to slow down digestion, to reduce the surge of blood sugar following a higher carbohydrate meal and maintain satiety for longer (1). I see/hear a lot of things about Glycemic Index and many of them are not factual, misguided or simply untrue. The most common myth I've heard lately is that all whole grains have the same Glycemic Index value as processed grains (it varies a lot, some do , some don't - see below). Besides the fact that one should be using the Glycemic Load and ditching the Glycemic Index, it's hard to substantiate those rumors - I don't like to call out web sites, simply type into google "whole wheat same GI as white wheat" if you want to see the numerous websites passing around this myth. If you would like a reliable source regarding general Glycemic Indices, try this Ha...