I have longed to talk about the risks and benefits of the Paleo diet but I did not want to publicly criticize another diet (it's one of my rules). However, I feel you should have the research so you can make an informed choice when choosing a diet.
Last week I was asked by Today Extra (Nine Network, Australia) to comment on new research about the Paleo Diet. So I jumped at the chance to clarify the good, the bad and the sometimes dangerous aspects of this popular diet. I spoke with hosts Sonia Kruger and David Campbell:
Paleo- It's one of the most popular and controversial diet trends on the market, recommended by top celebrity chefs who wax lyrical about its benefits.
But new research has found it might actually be doing devotees more harm than good....placing health and waistlines at risk.
Joining us with more is nutritionist Karen Fischer.
Q1.Karen, first of all for those of us who don't know, what is the paleo diet?
The paleo diet favours heavy doses of meat and protein, vegetables, eggs, nuts and fish, but outlaws grains, dairy, legumes, processed food, coffee, refined sugar and alcohol consumption.
Q2. A recent study on the paleo diet had some pretty surprising results...what did researchers find?
A Melbourne University study has found that following the caveman-style diet for just eight weeks can lead to rapid weight gain, health complications and an acceleration of pre-diabetes symptoms for those already overweight.
Results from animal tests originally intended to demonstrate the benefits of a low-carbohydrate, high-fat diet stunned the scientists when they actually resulted in a 15 per cent weight gain and rising insulin levels (Lamont et al 2016).
According to a report by the Sydney Morning Herald, "Researchers took two groups of overweight mice with pre-diabetes symptoms and put one group on a low-carbohydrate, high-fat diet. The proportion of fat in their diet increased from 3 per cent to 60 per cent. Their carbs were reduced to only 20 per cent. The other group ate their normal diet. After eight weeks, the weight of the Paleo mice ballooned by 15 per cent and their fat mass doubled from 2 per cent to almost 4 per cent." (Choahan and Calligeros 2016)
"We are told to eat zero carbs and lots of fat on the Paleo diet. Our model tried to mimic that, but we didn't see any improvements in weight or symptoms," Professor Andrikopoulos said. "In actual fact, they gained more weight, their blood sugar levels were higher, their glucose was even worse." Researchers believe the results would be mirrored in humans, because of the similarities in mouse and human genomes.
Similarly, another study of more than 120 000 people revealed that eating red meat significantly increases the risk of premature death from cancer and heart disease. Researchers from the Harvard School of Public Health concluded that eating as little as 85 grams per day of unprocessed red meat increases the risk of death by 13 per cent.
Frequent consumption of processed meats is even worse, increasing premature death by 20 per cent - that is the same as if you were smoking cigarettes ( Pan et al. 2012). Therefore according to this research, the paleo diet, which favours high meat consumption, is not the healthiest option,
If you want to eat meat... moderate meat consumption is fine (see end of article for amounts and portion sizes).
Q3. But paleo cuts out sugar, grains and processed food? So what was the weight gain put down to?
The Paleo diet is high in unhealthy, saturated fats and there are certainly unhealthy versions of this diet, which are high in acids and low in alkalising vegetables.
Fat needs to be burned off with exercise or else you will store it. So if you put an individual who is already not exercising a lot on a low-carb, high fat diet, they don't have the ability to burn the additional fat they are eating so they gain weight.
If you are pre-diabetic- you need to be careful with the amount of fat and protein you are eating. Consuming too much protein can put strain on your kidneys, so if you do choose to follow this diet make sure you get regular check ups at the doctors to monitor your kidney and liver function via blood tests. Do it monthly.
"What concerns me the most with the paleo diet is eating too much meat, especially red meat, increases the risk of cancer and heart disease - but you may not know it's damaging your health until severe symptoms appear, ie heart attack or cancerous lump."
"Let's not forget that cavemen rarely lived beyond their forties."
Q4. What sort of diet should we be following then if we want to kick start our health and maybe lose a bit of weight?
Researchers found when you swapped a high protein diet for one that is rich in vegetarian protein there were no increased health risks. So ensure you have plenty of vegetarian meals throughout your week. For example, have three vegetarian days per week or more if you can.
More information below:
Patient Case Studies
From a practitioner's perspective I have seen patients who were recommended high protein low/no carb diets (including Paleo, Gaps and Atkin) who have suffered side-effects and have come to me for help.
Their side effects included infertility (loss of periods), constipation from not enough fibre in the diet, and markers of early kidney and liver damage.
I have seen children who have been placed on high protein diets (by other practitioners) end up with kidney damage. One patient was close to having kidney failure according to her doctor. This child was eating meat with breakfast, lunch and dinner.
The kidney damage reversed once the child was placed on a diet low in meat (as the child also had eczema, we then place the child on The Eczema Diet with supplements for her eczema - this diet is liver cleansing and has a moderate to low amount of meat so it's safe for the kidneys).
How much meat and protein is okay for good health?
If you want to eat red meat and poultry, favour TWO serves or less of each per week, and remove the fat, including the chicken skin. This is especially important if you have eczema and other skin problems - saturate fat will make your skin worse, so low fat protein is your best option.
The portion size should be no bigger than the palm of your hand (ie a child-sided hand when serving meat to a child). Similarly nuts, whole grains and seafood were all considered better substitutions for red meat with a 7-19% lower mortality risk. (Pan et al 2012)
Safe fish consumption
How do I avoid high levels of mercury in fish?
Larger fish such as fresh tuna, flake and shark are high in mercury so it can lead to infertility and mental health issues.
The general rule is the higher up the food chain and the bigger the fish, the more mercury it may contain.
Seafoods such as trout, flathead, small fillets of dory, hake and quality canned tuna in spring water/brine are low in mercury. If you do eat a large fish that is high in mercury such as a large snapper, fresh tuna, swordfish, marlin etc., the Australian Government Guidelines suggest you avoid seafood for 2 weeks to allow time for your blood mercury levels to reduce.
Is high meat and high fish consumption an environmental issue?
Yes, I believe so. As the population increases and some of that population gets wealthier, meat consumption is predicted to double (Mosley 2014). According to Dr Michael Mosley, almost a third of the Earth's farmable land is devoted to raising livestock and 30% of the crops we grow are to feed the livestock.
The UN Food and Agriculture Organisation estimates that livestock accounts for 14.5% of man-made greenhouse gas emissions (the same amount emitted by all motor transport such as cars, planes, boats and trains!).
Our oceans are also in trouble. The Sustainable Seafood Guide estimates that up to 80% of the world's fish stocks are over exploited. Particularly in trouble are larger fish. Watson, a scientist at the University of British Columbia, asserts there is not enough fish to meet current and growing human consumption (Berry 2012).
Be mindful of the sustainable food sources - this is as simple as eating more vegetarian food and less animal products.
Wholegrains and your health:
The paleo diet excludes legumes and wholegrains. Vegetables, fruits and nuts give us some soluble fibre (not a lot). However, we also need insoluble fibre, which we get from foods like wholegrains and quinoa. Insoluble fibre helps keep our bowels moving.
Vegetables are not a good source of fibre. Most veggies contain virtually no fibre (except for potato, sweet potato and carrots). People falsely assume they are getting enough fibre but it's not possible without eating some form of grains, legumes or quinoa and other grain-like carbohydrates.
Whole grains and legumes also provide many essential macro and micronutrients, as well as cancer-fighting phytonutrients. The strongest research suggests that whole grain foods should be included in a healthy diet and lifestyle program (Jonnalagadda et al 2011).
If you want to read more about the studies regarding the paleo diet and the red meat study, the links are below:
Lamont, B., Waters, M. and Andrikopoulos, S. 2016, A low-carbohydrate high-fat diet increases weight gain and does not improve glucose tolerance, insulin secretion or β-cell mass in NZO mice, Nutrition & Diabetes, issue 6, no. 194, doi:10.1038/nutd.2016.2, Published online 15 February 2016, viewed 20 February 2016,
Jonnalagadda, S. Harnack, L. Hai, R. McKeown, C. Simin, L. and Fahey, G. 2011, Putting the Whole Grain Puzzle Together: Health Benefits Associated with Whole Grains—Summary of American Society for Nutrition 2011, The Journal of Nutrition, vol. 141, no. 5, May 1, viewed 1 March 2016.
Pan, A. Sun, Q. Bernstein, AM. Schulze, MB. Manson, JE. Stampfer, MJ. Willet, WC. and Hu, FB. 2012, Red meat consumption and mortality: results from 2 prospective cohort studies, Archives of Internal Medicine, issue 172, no. 7, 9 April, viewed 1 March 2016, doi: 10.1001/archinternmed.2011.2287.
Paleo and red meat articles with links:
Brown, R. 2016, Paleo diet touted as better for diabetics could cause rapid weight gain, research finds, ABC News, 19 February, viewed 1 March 2016.
Harvard Health Publications, n.d, 'Cutting red meat for a longer life', retrieved 1 March 2016.
Fischer, K. 2012, The Eczema Diet, Exisle Publishing, Wollombi.
Berry, S. 2012, Endangered eats, Sydney Morning Herald, 10 October, viewed 1 March 2016.
Mosley, M 2014, Can eating met be eco-friendly? BBC Horizon, 20 August, viewed 1 March 2016.