How Da Vinci Made the Modern World Possible

One of my favorite dog breeds is extinct because of Leonardo da Vinci...

In the 16th century, enterprising Brits devised a way to continuously rotate meat on a spit over an open fire without endangering human cooks.

They attached a large wooden treadwheel high up on the wall near the fire. A chain ran down from the wheel to the roasting spit, so that turning the wheel would rotate the meat.

The cook could force a dog called a turnspit inside this dog-sized hamster wheel and make it run while the meat cooked. Using turnspits for cooking became popular across Britain and beyond.

The turnspits did the work, but they didn't love it. The use of turnspits in kitchens led to the founding of the Society for the Prevention of Cruelty to Animals ("SPCA") in the 1850s. Even then, it was obviously a lousy life for a dog.

But the other reason is technological. Folks stopped using turnspit dogs – and therefore stopped breeding them, leading to their extinction in the late 19th century – because they found a better way to cook meat.

Leonardo da Vinci deserves the credit for the turnspit's obsolescence.

In the 1480s, the Italian artist and inventor sketched out a roasting spit in a fireplace. As he imagined it, rising hot air and smoke from the fire traveled up a chimney and turned a fan. A chain connected to the fan would turn the meat.

It took nearly 400 years for da Vinci's idea to take root in Britain. Once it did, though, the turnspit breed went from ubiquity to extinction in a matter of decades.

Da Vinci's "smokejack" was much more than just a win for animal welfare.

This concept of turning heat energy into motion – particularly, circular motion – has made the modern world possible.

First, the steam engine powered the early locomotives and factories of the Industrial Revolution. It worked by burning coal to heat water and using the pressure of the resulting steam to turn wheels.

Now, use that same steam to turn a turbine connected to a generator, and you've got electricity as produced by a modern coal plant...

Most forms of electricity come from motion – specifically, the movement of air and water. And a lot of that movement comes from heat... whether by burning coal and natural gas or via geothermal power.

Today, our country is in the midst of a huge energy transition. At the same time, we're facing an incredible surge in power demand. This unique setup presents an opportunity for us as investors...

Earlier this week, my colleagues Brett Eversole and Whitney Tilson sat down to detail why they're both so excited for the future of the energy sector. They explained that, despite the push toward renewable energy, oil and gas will remain in high demand for decades to come. And thanks to the growing use of artificial intelligence, energy demand will only soar from here.

They've even uncovered six new ways to profit from the upcoming commodity supercycle. With the energy sector at one of its cheapest levels in the past 50 years, all signs point to a massive multiyear rally that you won't want to miss out on.

Click here for the full details.

Let's dig into the Q&A... As always, keep sending your comments, questions, and topic suggestions to feedback@healthandwealthbulletin.com. My team and I really do read every e-mail.

Q: Does blending reduce the fiber in fruits and vegetables? – B.H.

A: Thanks for your question, B.H. A study from the University of Minnesota published last year found that "blending fruits or vegetables will not decrease fiber content, as dietary fiber does not decrease with mechanical forces."

So if you're blending produce for things like soups and smoothies, the amount of fiber will be the same as if you ate the whole fruit or vegetable. Blending can even make nutrients such as fiber easier to digest.

Blending might also improve your body's response to sugar...

A small study published in 2022 compared the glycemic response for participants who ate whole apples and blackberries with those who drank them in blends.

What the researchers discovered was that both men and women in the study had lower glycemic responses to the blended fruit than whole fruit. One reason might be that your body processes the fiber more quickly when the food is blended, which helps to slow the absorption of sugars.

We'd like to see more robust studies on this topic before coming to any real conclusions. But even without this added benefit, blending your produce isn't causing any harm... and may even be better than eating it whole.

Q: What type of milk should people be drinking? 1%, 2%, whole, etc.? Is there a difference between adults versus kids? Thanks. – R.M.

A: If you really enjoy drinking milk, R.M., stick to whole milk. The fat will keep you feeling full, and you'll get plenty of calcium and other nutrients.

If you opt for the low-fat or skim varieties, you won't get the calories. That sets you up to overeat to satisfy your hunger hormones.

However, milk has some downsides...

It contains a sugar called galactose that increases inflammation. As I've written before, inflammation is linked to many diseases, including heart disease, diabetes, and arthritis.

Lots of Americans grew up on the myth that you just need to drink milk and eat dairy to build strong bones. If you're in America, you might be familiar with the massive campaigns urging folks to drink milk.

Following the Great Depression, the government began promoting milk as a way to have "good teeth, vitality, endurance, and strong bones." The campaign was part of President Franklin D. Roosevelt's New Deal program. Not only did the promotion drive money to dairy farmers and support the dairy industry, but it also employed artists around the country to create the posters encouraging Americans to drink milk.

In 1993, the first TV commercial aired in the "Got Milk?" campaign that lasted for nearly a decade. (It was directed by Michael Bay... the guy behind many over-the-top, big-budget action movies.)

The campaign was the brainchild of an ad agency for the California Milk Processor Board. And its supposed purpose was to improve kids' health by getting them to consume more milk.

But be warned: Dairy alone doesn't guarantee strong, healthy bones. We also need...

• Vitamin D, which helps our body absorb calcium.
• Phosphorus, magnesium, potassium, and sodium, which are other essential ingredients in bone tissue.
• Protein, as it's crucial for bone development and building muscle.

Really, the best thing to do is skip milk altogether... I recommend getting calcium and these other essential ingredients from a variety of sources, including cheese, yogurt, fortified orange juice, leafy greens, and fish.

What We're Reading...

• Did you miss it? One thing that powers everything in finance.

• Something different: The Food and Drug Administration is finally pulling ineffective cold medicines from shelves.

Here's to our health, wealth, and a great retirement,

Dr. David Eifrig and the Health & Wealth Bulletin Research Team
November 8, 2024