Less meat, more plants
The easiest way to reduce your personal carbon footprint is to go vegan. Growing beef requires up to 100 times more land than growing peas or soybeans to produce the same amount of protein. I’ve reduced my meat intake to some local grass-fed organic red meat or a rotisserie chicken as an occasional treat once or twice a month. This allows me to enjoy meat as part of my diet on a more sustainable level.
Studies have shown no difference in gut health between vegans, vegetarians, and occasional meat eaters. The most important dietary factor we found for better gut health was the number of different plants we eat weekly, with 30 per week being the optimal number.
That may seem like a lot until you realize that this also includes mushrooms, spices, nuts, seeds, herbs, and legumes. Simply using a stir-fry base of onions, garlic, olive oil, and carrots when cooking, adding a bean or lentil mix to pasta sauce or a cooking spice mix, or sprinkling mixed nuts and seeds in yogurt can increase quickly this number.
Ditch the alternatives to ultra-processed meat
Unfortunately, many vegans rely too much on ultra-processed foods that are high in salt and fat that are bad for us and the environment (some are produced in large, energy-intensive factories). Newer production methods, such as cell-grown “meat,” “fish” and even “cheese,” are on the horizon and likely to be more environmentally friendly.
Brands like Symplicity (currently supplying restaurants across the country and soon to be available to consumers) use large containers to ferment organic vegetables with no artificial additives, making “meatballs” and “burgers” that benefit our gut microbiome with almost no waste.
Choose legumes over animal protein
We care too much about protein. It is legumes, beans and lentils that help the centuries-old populations of some cultures survive the rest of us. This is due to its high content of fiber, protein, minerals, and polyphenols (polyphenols are the plant chemicals that help our gut microbes).
We need iron and iodine, zinc, and vitamin B-12 to be healthy, but most of us can easily get them from eggs, clams, or clams and chicken, the most sustainable livestock products, once a week.
In 2017, I visited the Hadza people of Tanzania and dramatically improved the diversity of my gut microbiome in just three days. eating all the plants and seeds, fruits and nuts they eat in a week, along with the occasional hedgehog.
Go organic, even a little
Herbicides were generally considered safe until we realized the importance of microbes, both to the soil and to our guts and immune systems. Our own data has shown the power of a healthy diet and microbiome to protect against serious disease.
Pesticides and herbicides are designed to disrupt natural ecosystems, reduce biodiversity and degrade our soils, affect our aquatic life and the survival of insects. We consume these chemicals in small amounts every day and they are hard to avoid, especially on a plant-based diet.
Although it is beneficial to only buy organic food when possible, the current level of organic farming is insufficient to produce enough food for all of us. And that’s not to mention the price difference. Buy local and seasonal ingredients that stay fresh longer. It pays to prioritize certain foods: I always buy organic strawberries, oats, spinach and apples, as non-organic varieties tend to have the highest levels of herbicides.
Cook smarter (and microwave)
We can reduce fuel consumption for cooking and preserve beneficial chemicals in food by harnessing the power of microbes to ferment and preserve leftover vegetables.
Kimchi, for example, uses cabbage, green vegetables, garlic and chili, while heating food in a microwave saves energy and preserves nutritional content. Now I microwave a whole potato instead of baking it, and I also steam spinach in the microwave. I make vegetable soups, ferment leftover vegetables (such as sauerkraut or beets), such as the tough outer leaves of cauliflower, and freeze fruit that softens.
Fish has been overrated
The science of fish has changed, and it is now clear that the health benefits of fish and omega-3 fats have been exaggerated. Studies of omega-3 supplements show no clinical benefit unless you’re pregnant or have had a recent heart attack, and fish is less beneficial for your heart than we thought. Furthermore, most of the fish we now eat in the UK, including salmon and trout, comes from unsustainable aquatic farms.
Use a local fishmonger or supermarket fish counter that you trust and can ask questions about. Clams and clams are healthy, largely sustainable, and very tasty.
The dairy dilemma
Dairy products are a massive cause of global warming and their health benefits, such as improving calcium intake and strengthening bones, have been exaggerated. There are many better sources of calcium, including sesame and tahini seeds, dark green leafy vegetables, and chalky tofu. While dairy alternatives are generally better for greenhouse gas emissions, they can cause other problems; the excessive amount of water used to create almond milk and its harmfulness to, for example, bees. Others, like soy and oat milk, can be highly processed.
Personally, the only milk I haven’t given up on is fermented milk, known as kefir, which I make myself and take a small dose every day for my gut microbiome.
Make it personal
The fact is that there is no diet that suits all of us. But the rapidly growing field of personalized nutrition (led by companies like ZOE, which I co-founded) suggests that by predicting which foods are best for our bodies, we can reduce spikes in blood sugar and fat and improve our gut health. We can feel better, have more energy and feel less hungry, all without talking about calories.
But while we wait for technology, including apps, home tests, and continuous glucose monitors, to help us eat healthier, we can make positive changes by following the general approaches outlined here. In the meantime, listen to your body and eat more than feels good.
Take a break
No one is perfect, and the enjoyment of food and the social interaction that comes with it can be just as important as environmental and health considerations. Even small positive changes can go a long way.
Tim Spector’s Food for Life is published by Vintage (£20). To support The Guardian, order your copy for £17.40 at guardianbookshop.com. Join the waitlist for the ZOE app at joinzoe.com