Biting back over the vegan substitutes health trap (1)
Veganism isn’t about human health, it is about animal health: if you don’t breed, enslave, slaughter, skin and eat animals, they tend to stay healthier (30 October, p 38). Your article never mentions that veganism isn’t just about food, but also clothes, make-up, hair products, pharmaceuticals, ceramics, weapons and pretty much everything else.
Better human health would be a pleasant by-product of veganism, but it is by no means the goal. Maybe you are confusing the philosophy of veganism with what adherents call “plant-based diets”, which are all about human health.
Biting back over the vegan substitutes health trap (2)
Your article on vegan substitutes draws on flaws in dietary science that were pointed out in an article you published two years ago (13 July 2019). This showed how most dietary advice is based on observational studies rather than randomised, controlled studies, a state of affairs that leads to contradictory guidance on things like salt, sugar and fat.
You cite more observational studies about “ultra-processed foods”, which of course have the same weaknesses explained in your earlier article. I suspect the real reason for the adverse effects of vegan substitutes is that people like them and so eat too much.
The climate crisis is just a tragedy of the commons (1)
One phrase that doesn’t seem to be used enough in the context of the COP26 summit and climate change is “the tragedy of the commons” (30 October, p 8). This describes a scenario that is a standard part of mathematical game theory.
The “tragedy” considers free public use of a common resource 鈥� for example, community-owned land for grazing cattle. In that case, the community’s interest is best served by controlling use to the level that optimises grass growth. However, each individual cow owner does best if they maximise the amount their cattle eat. Their loss because of the degradation due to their minor contribution to overgrazing is swamped by the extra resources they gain.
The only solution to this is collective management of usage. The trouble with climate change is that the world has no mechanisms for truly effective collective control.
The climate crisis is just a tragedy of the commons
Having read several pages on COP26 and the need to cut emissions, I was struck by the irony of a story on the next page reporting advances in restoring male fertility (p 13). The largest contribution an individual can make to reducing carbon emissions is to not have a child.
Rooting for Finland's tree-based circular economy
Graham Lawton’s article “A wooden circular economy”, on Finland’s research and development of a cyclical symbiosis of woodlands, forestry and wood technology, was life-affirming and full of hope for the future (30 October, p 21). Finland demonstrates one way forward that embraces the beginning of a new age of wood and the coming of sustainably sourced timber to reduce carbon emissions and the destruction of Earth’s primordial ecosystem.
How to make heat pumps more attractive
Coupled with insulation and draughtproofing, heat pumps are very good for warming buildings sustainably, but they cost more than boilers and are more complicated (23 October, p 9). While reliability is excellent, repairs by skilled technicians (if needed) are costly. And knowing how to run a heat pump optimally is difficult when every half an hour.
Our solution, laid out in our Institute of Refrigeration paper , is to lease a heat pump, not buy one. This keeps the supplier responsible for maintenance, repair and end-of-life replacement. As with district heating, householders should pay the heat pump provider a price per unit of heat delivered, letting them source the electricity.
Horse origin may shed light on a bigger mystery
Your article on the possible origin of domesticated horses has some important wider implications (30 October, p 18). These relate to the realisation that languages as diverse as modern Welsh and classical Sanskrit have a common root, which has led to a search for the origins of a .
There are strong suggestions that it was spoken in an area north of the Black Sea and Caspian Sea at least 5000 years ago. Yet there is no genetic trace or historical record of a conquering or trading people from this area back then, so speculation about their mobility, spread and cultural dominance has involved everything from their having invented the wheel to their domestication of horses.
Your report that DNA analysis shows the first domesticated horses were present in this area at this time is therefore very striking.
Issue of Indigenous land in the US runs very deep
Regarding Annalee Newitz’s look at the truth behind land used to fund some universities in the US 鈥� that is to say, the fact that it was taken from Indigenous people (2 October, p 26). My understanding is that pretty much all land in the US was stolen from these people, either by fake treaties, massacres, forced deportations and/or disease 鈥� sometimes spread accidentally, sometimes deliberately.
It is great that some universities are trying to make reparations for this, but what about the owners of the rest of the land?
Turn your food waste into a tasty 'rubbish soup'
When it comes to reducing food waste, we often put vegetable peelings in a pressure cooker (a great energy-saving device) with some water, herbs and garlic to make a healthy vegetable broth we call “rubbish soup” (25 September, p 42).
We keep the strained liquid and put any remaining solids in the compost, working on the principle of “use as much as you can before you bin it”. Perhaps readers have other creative ideas or recipes.