Vitamin D is the one supplement that would be paleo. At least it would be for those of us that don't live outside year round. You can have your D level measured. The low RDAs only prevent definable deficiences, not problems that take a long time to develop. Michael Holick, MD is a leading writer on this subject. This is a 10 page PDF: Vitamin D: importance in the prevention of cancers, type 1 diabetes, heart disease, and osteoporosis and its companion Sunlight and vitamin D for bone health and prevention of autoimmune diseases, cancers, and cardiovascular disease [change PDF to 100% to read]. Or if you prefer, there is an hour video on YouTube.
The digestive abilities of anatomically modern humans, however, are different from those of Paleolithic humans, which undermines the diet's core premise. During the 2.6 million year-long Paleolithic era, the highly variable climate and worldwide spread of human populations meant that humans were, by necessity, nutritionally adaptable. Supporters of the diet mistakenly presuppose that human digestion has remained essentially unchanged over time.
Grass-fed beef is often highlighted on the diet, which is promoted to contain more omega-3 fats than conventional beef (due to being fed grass instead of grain). It does contain small amounts of alpha-linolenic acid (ALA), a precursor to EPA and DHA. However, only a small proportion of ALA can be converted in the body to long-chain omega-3 fatty acids (EPA and DHA). The amount of omega-3 is also highly variable depending on the exact feeding regimen and differences in fat metabolism among cattle breeds.  In general, the amount of omega-3 in grass-fed beef is much lower than that in oily marine fish.  Cooked salmon contains 1000-2000 mg of EPA/DHA per 3-ounce portion, whereas 3 ounces of grass-fed beef contains about 20-200 mg of ALA.
The CrossFit Games is an athletic competition sponsored by Crossfit Inc. and Reebok. The competition has been held every summer since 2007. Athletes at the Games compete in workouts that they learn about hours or days beforehand, consisting mostly of an assortment of standard aerobic, weightlifting, and gymnastics movements, as well as some additional surprise elements that are not part of the typical CrossFit regimen such as obstacle courses, ocean swimming, softball throwing, or ascending a pegboard. The CrossFit Games stylizes their individual winners as the "Fittest on Earth".
In that sense, Whole30 has been so helpful in understanding my body. So how am I eating now? I would say that I'm eating pretty "paleo" these days. I definitely still indulge once in a while, with some red wine or french fries, but I haven't been tempted to binge in the slightest. I would definitely do Whole30 again, but I need a bit of a break from it at the moment. Instead, I'm ready for a mindful and moderate approach to my new chapter of life, back in New York City.
Life Without Bread: How a Low-Carbohydrate Diet Can Save Your Life by Christian B. Allan, Wolfgang Lutz. It is based on Dr. Lutz's work with thousands of patients in Austria. It deals with the health issues connected to high carb consumption. It is basically an English version and update of Dr. Lutz's 1967 book with the same title: Leben ohne Brot. He recommends eating only 72 grams of carbohydrates, and an unlimited amount of fat. And provides evidence as to why this is the healthiest diet. Read the review at Amazon by Todd Moody (it will be first!). See excerpts from his earlier edition: Dismantling a Myth: The Role of Fat and Carbohydrates in our Diet
When the clock struck midnight, I couldn't wait any longer: I helped myself to a serving of plain white rice. I sat on my couch cross-legged, eating each spoonful with my eyes closed like one of the yogurt commercial ladies. I even smiled. The next day, I ate more gluten-free carbs, like rice and paleo pancakes. I also had wine and tequila, a grain-free liquor option. I didn't get bombed like I was worried about, but I did have a worse-than-usual hangover the next day. The fun night out was worth it, though.
So what does the science say about the paleo diet? Some research suggests that the health claims hold truth. A review analyzed four randomized, controlled trials with 159 participants, and researchers found that the paleo diet led to more short-term improvements in some risk factors for chronic disease (including waist circumference and fasting blood sugar) compared with other control diets. (4)
According to the CDC, cardiovascular disease is the number one cause of death in the United States. Interestingly however, our Paleolithic ancestors and contemporarily studied hunter-gatherers showed virtually no heart attack or stroke while eating ancestral diets. The references below will explore these facts to better help you understand the heart-healthy benefits of a Paleo diet.
A metaresearch group at Tilburg University in the Netherlands investigates scientists’ research methods and operations, scrutinizing questionable practices such as selective reporting of statistical tests and data massaging. The group instead advocates for practices such as preregistering studies and making experimental data immediately available for open external review and verification. Its members are optimistic that “the perverse incentives of careerist academia, to hoard data and sacrifice rigor for headline-generating findings, will ultimately be fixed.”