As a Registered Dietitian (RD) that is openly paleo and advocates a paleo lifestyle in practice, I often get inquiries from other RD’s questioning the efficacy, safety, recommendations and/or overall idea of paleo. I recently received an email from one such RD and am going to take this opportunity to address the question and concerns presented. Here is the note that I received in its entirety:

Hi Amy,

I read some of your articles and found them to be helpful. I still have some questions that maybe you might be able to answer. “Avid Paleos” that I overhear sometimes will say that your body has to shift from using glucose as energy to using ketones as energy; however, how could they be in ketosis while consuming plenty of CHO from fruit, etc? Is this just misinformation on their part?

Also, one person in particular said that “someone told her” that she must eat copious amounts of CHOs of any kind from morning to noon one day per week to prevent “thyroid burn-out,” which I thought was absurd. Any insight?

What is the reasoning behind restricting dairy, or natural whole grains (oats, barley?) for that matter? While I commend many aspects of Paleo, I just cannot see the destruction caused by obtaining calcium from low-fat or fat-free milk, for example. I’d like a more in-depth explanation as to the physiological implications of consuming these foods as it relates to Paleo. I also see many Paleo-followers having to consume tons of artificial supplemental nutrition cocktails from GNC in order to meet their nutrient needs, which seems to violate the very principles on which Paleo stands…?

These are the details I’m getting stuck on, and I don’t have any evidence to dispute or confirm these seemingly crazy claims. I’ve attempted to do my own research, but I have come up with very little. I’m desperate for more information than that of “layman’s advice” I can get from random Paleo-backing sites. Evidence-based information would be SO VERY appreciated! Please help me understand so I can better serve my patients! Thanks!

Okay, let’s break this down one paragraph at a time –

“Avid Paleos” that I overhear sometimes will say that your body has to shift from using glucose as energy to using ketones as energy; however, how could they be in ketosis while consuming plenty of CHO from fruit, etc? Is this just misinformation on their part?

This is largely misinformation. It is true that if dietary carbohydrate is restricted to <10% of caloric intake (usually <30 grams/day) and protein levels are kept moderate; the body will ‘shift’ into ketosis. However, this may take anywhere from 3-7 days of very low carbohydrate eating to occur. If the individual is getting higher amounts of carbohydrate via fruit and vegetable sources, entering a ketotic state is not likely. Often paleo is viewed as a low-carb diet, and while it can be; that is not necessarily always the case. Not all paleo followers are running on ketones! In fact, the paleo lifestyle may incorporate starchy vegetable based carbohydrate in the form of sweet potatoes, yams, winter squash, and other roots and tubers in order to meet performance and energy needs in certain cases (athletes, lean individuals, etc.).

Also, one person in particular said that “someone told her” that she must eat copious amounts of CHOs of any kind from morning to noon one day per week to prevent “thyroid burn-out,” which I thought was absurd. Any insight?

Again, this is a case of misinformation – there is quite a bit of it out there and I would encourage you to do some homework before believing what these individuals tell you. The idea that anyone needs to – or should – eat copious amounts of ANYTHING is absurd! I would question this individual’s reasoning and dig deeper into her current health/thyroid status and her diet. If she has been adhering to a very low carbohydrate, calorie restricted diet and/or has been in ketosis for a long period of time it may be more beneficial to remove herself from that state. And, in a sensible manner incorporate reasonable (not ‘copious’) amounts of plant based “safe starch” carbohydrates.

What is the reasoning behind restricting dairy, or natural whole grains (oats, barley?) for that matter? While I commend many aspects of Paleo, I just cannot see the destruction caused by obtaining calcium from low-fat or fat-free milk, for example. I’d like a more in-depth explanation as to the physiological implications of consuming these foods as it relates to Paleo. I also see many Paleo-followers having to consume tons of artificial supplemental nutrition cocktails from GNC in order to meet their nutrient needs, which seems to violate the very principles on which Paleo stands…?

First, I would like to recommend that you pick up copies of both The Paleo Solution and The Paleo Diet; the reasoning behind paleo recommendations are fully explained AND referenced in both of these. Additionally, even if you are not sold on “paleo principles”; as a nutrition and health professional I would highly recommend that you learni more about styles of eating other than the traditional USDA Food Plate method. It is our duty, as educators and practitioners, to provide our clients and patients with information on all types of diets and diet practices. I read MANY non-paleo research articles, books, and blog posts so that I am able to explain both the pros and cons of ALL eating styles. You may find this extremely beneficial in the advancement of your career and your success with clients. To address your questions, I will explain things in simple terms and if you would like a deeper explanation and scientific references the books that I have recommended are great resources as is this handy website.

The foods that are not part of a paleo lifestyle; grains, legumes, soy, dairy, etc, all contain proteins and/or anti-nutrients that our bodies were not designed to handle. Grains contain large protein molecules called ‘lectins’. The digestive system doesn’t have the ‘equipment’ necessary to breakdown lectins, which means, they just hang around in the gut. These ‘loose canons’ have the ability to bind to certain gut receptors and then act as ‘keys’ unlocking a door that lets them out into our bodies. Unfortunately, lectins were ‘born in a barn’ – not only do they not close the door as they leave, but they also damage the gut on the way out. This is how the gut gets ‘leaky’ and it doesn’t end there. Since the lectins are not part of the ‘normal’ environment, the body doesn’t recognize them and the immune system, standing on guard, initiates an attack on the strangers creating antibodies against them. The antibodies made have a striking resemblance to other proteins normally found in our systems. This leads to an autoimmune response (the body attacking itself). The story is similar for legumes and dairy both of which also contain proteins, anti-nutrients and protease inhibitors that irritate the gut in much the same way as lectins. While many may feel exempt from the whole process, claiming that they feel fine – this may not necessarily be the case. While some may be more sensitive to these foods than others, it is likely that removing them will have positive effects across the board.

You specifically mention low-fat and fat free dairy. These are particularly conspicuous as one of the most beneficial components in dairy is CLA (conjugated linoleic acid). CLA has been found beneficial in the prevention of cancer, CVD, hypertension, elevated blood lipids, weight loss, osteoporosis, inflammation, insulin resistance, and immunity. The CLA in dairy is housed in its fat component. When the fat is removed, as is the case in low fat and fat free dairy products, you are basically left with insulin spiking sugar (lactose), along with a bit of protein and calcium. Remember that milk is “fortified” with Vitamins A and D – they aren’t naturally there. To address the calcium issue, it is well known that dairy is not the only source for this mineral. In fact, some of the best sources of calcium are sardines, trout, salmon, etc, and these protein rich sea creatures also contain long chain omega 3 (DHA) fatty acids, and a plethora of other nutrients. Additionally; chard, kale, broccoli, spinach and many other vegetables are sources of the mineral too and are also rich in many other nutrients.

As far as the need to “consume tons of artificial supplemental nutrition”; if the individual is truly following a paleo protocol this should be completely unnecessary. In fact, this idea is exactly the opposite of what is recommended. While supplements such as fish oil and vitamin D do make good additions, if the individual is healthy and eating solid, high quality fare there is little need for much else in the way of supplements. I challenge you to say the same when considering the SAD diet.

I hope that I have answered your questions and I highly encourage you to continue researching on your own. The books mentioned are a great place to begin – and if you’re up for a life changing experience; I challenge you to give it shot for yourself. I wasn’t a believer from the word ‘go’, but I did the research, tried it and haven’t looked back since.