One of the main reasons the Paleo diet appeals to so many people, especially men, is that no one has to give up their long time favourite food – meat – the star of almost every meal. For decades we have known that eating more vegetables is where good health is really at. Yet people love their meat. It’s star shines so brightly due to so much wonderful (but unscientific) marketing.
A diet that encourages more meat has instant appeal.
We all know that eating more meat results in higher protein in the diet. The paleo crowd state this is a major benefit of the diet. This is a major reason that it appeals to weight trainers – because
a lot of meat = a lot of protein = the ability to grow a lot more muscle.
Simple. But is that the whole story? Is that all the matters?
And, as an aside, have you noticed that when people want to LOSE weight, they are encouraged to eat more protein – and when they want to GAIN weight – it’s the same. The same shake is supposed to help you lose or gain weight! Someone must be wrong!!!!
Is a lot of Protein really a good thing?
But science shows something quite different. Despite the Western world’s love affair with protein in the 1940s and ’50s, we now know that eating more animal protein increases the levels of insulin-like-growth factor-1 (IGF-1) in the blood. Why does this matter? Because IGF-1 is a hormone designed to send messages to the organs to grow.
Terrific! Say the weight lifters! More muscles!
However, the ‘Grow’ message is not all good when you are already a full grown adult.
Science showed back in the 1940s exactly how much protein we need to take in to maintain our body weight, replace old cells, heal damaged cells, produce all the proteins needed for our metabolism to keep chugging along and keep the immune system functioning well. This was made into a “recommended daily intake” (RDI), or “recommended daily allowance” (RDA) in some countries. The RDI for protein is about 46g/day for women and about 64g/day for men (up to 70 years old). This level is easily obtained without eating more meat, in fact, you can quite easily reach this protein level on a plant-based diet without eating ANY meat.
Paleo diets generally end up with people eating 2 and 3x the RDI for protein.
What happens when we eat above the RDI of protein is this: Lots of animal protein is like dumping a box of Lego in front of a child. The body says – “Whoa – all these building blocks. We’ll have to build some things.” The liver responds by pumping out plenty of IGF-1 hormone to send messages to cells that it is ‘growing time’. The problem is – as an adult – we don’t need a lot of growing to happen, especially when some of that ‘growing’ ends up being tumours growing.
Excess animal protein fuels cancer
That sounds a bit far-fetched, doesn’t it. Not really. Even though this excess protein may result in you being able to bench-press more kilos of iron, it has been shown both in the lab and in animal and human trials over 3 decades of research, that raising animal protein levels to 20% of the diet stimulates tumour growth at all its stages. Getting animal protein below 5% of the diet is the only way to switch tumour growth back off, and the more animal protein a person has consumed in their lives, the harder that becomes. Paleo diets commonly have people eating animal protein at levels of 50% and even 70% of their diet.
Animal protein is strongly implicated in our most common cancers, partly because of this IGF-1 mechanism. That’s a scary thing that doesn’t get much mention in the Paleo recipe books. Interestingly, whole-food plant proteins do not raise IGF-1 levels or lead to tumour growth.
“But modern Paleo is not all meat – it’s actually lots of greens!”
You hear popular Paleo presenters telling their followers that Paleo is not about meat – it’s about green leafy vegetables – and they show huge shopping baskets full of greens. Is this how Paleo works in reality though?
In real life, you cannot sustain your energy levels on non-starchy vegetables and only a palm sized portion of meat in a day – while eating no starches such as grains or beans. That is not enough calories. You would soon feel weak and lethargic. Since grains and beans are on the paleo NO list, the only choice you then have is to either eat more fat (which is popular in many circles – a real problem in itself – explanation coming up), eat more meat, fish or eggs (the usual choice for most Paleo followers), or use stimulants like coffee to give you the energy the starches in grains or beans could otherwise have provided. Eating a large salad or steamed vegetables at each of 3 meals alongside a palm-sized portion of meat is still way over the RDI of protein. But if you cut back the meat to the RDI and only eat the vegetables, you’ll be hungry. Paleo just doesn’t work as a healthy diet – you have to eat an unhealthy amount of animal protein to make it work.
I expect that in 20 – 30 years time, we will see a huge rise in cancer rates due to the current popularity of paleo diets and their penchant with more meat.
What about if I select free-range, wild or organic meat?
I think everyone agrees that eating meat with fewer chemicals and hormones in it is always better. However, in the paleo world there is a belief that eating organic or grass-fed in some way mitigates the effects of eating too much meat.
I have heard the argument that “all the research on meat refers to commercially bred meat”.
This isn’t true.
The problem with meat – with too much meat – is not primarily whether it comes with chemicals (although it is good to avoid these as much as possible). The issue with health and meat is that it contains:
- too much protein
- too much heme-iron
- too much saturated fat
- no anti-oxidants
- no fibre
- precious few phytonutrients
Even organic or grass-fed meat contains the same protein, iron and fat (sometimes a little less fat, but nothing like the fat of the actual paleo days when wild animals were generally lean and sinewy), and the same lack of fibre, antioxidants and phytonutrients. Eminent researcher Walter Willett, the Chair of Nutrition at Harvard University, said that there is no safe level of red meat, the same as there is no safe level of radiation. Startling words from a nutrition professor.
We’ve talked about the problem of excess protein.
Excess iron rusts – in the body
What is the problem with excess iron – after all, high iron levels is one of red meat’s primary marketing points! The answer is that excess iron being absorbed causes causes oxidative stress (this means that it ‘rusts’), requiring more anti-oxidants to mop up the resulting free radicals before they damage DNA.
Saturated fat is also real problem with meat. Meat cannot be separated from the fat as fat is in each muscle. Why is this a problem? See the next post.
The lack of fibre, anti-oxidants and phytonutrients in meat, whether free range, organic, wild or commercially bred, makes me wonder why anyone wants to make it a mainstay of a diet?
To call any meat a ‘healthy choice’ is just marketing hype.
After reaching the low protein RDI, it simply isn’t healthy to eat more meat, regardless of how the animal was raised.