My father had died when I was young, so if I didn’t acknowledge my mother’s birthday, likely no one would. On her birthday, I decided to bake her some cookies, take them to her house and leave them with a little note for her.

But what to write about? My mother and I had not always been close. Pouring out words of love seemed insincere, but there were plenty of things I did appreciate, so I wrote a letter expressing my appreciation for what she had taught me. She taught me to live within our means and not to go into debt. She taught me the color of someone’s skin was irrelevant. She taught me helping others in need was its own reward. She taught me to value the elderly. She taught me how to see the shapes in the clouds. She taught me to appreciate the way the air smelled after a rain.

Having finished the letter, I sent the cookies and the handwritten letter to my mother. That evening, she called and thanked me, saying it was a wonderful birthday present.

Two years later, she suffered a fatal heart attack. While cleaning out her house, I came across a photocopy of the birthday letter I had written to her in the drawer of the bedside table in the guest room. And then room after room, drawer after drawer revealed more photocopies of the same letter. There was one in the kitchen drawer and one taped to the inside of the kitchen cabinet. I also found one in a drawer in both bathrooms, another in the living room and two more in her bedroom.

Finally, I opened the drawer beside her bed, where I found an old handkerchief and as I pulled it out, a wrinkled piece of paper fluttered to the floor. It was the original birthday letter. It had been smoothed over and over again. I realized at that moment that the best things I could have given my mother weren’t really things at all.

Environmental groups and rock climbers are always at loggerheads because of the effect of rock climbing on the environment. There have been many examples, wherein rock climbers are accused of going into natural reserves and treating the animals, plants and rocks there badly. However, with the changing times, rock climbers are conscious and carry out minimal climbing.

Rock climbers hammer bolts on climbing routes and in the process damage the nature of rocks. In addition, climbing activities also have an effect on the animals and plants situated near the climbing area. The plants growing near the base of rocks are trampled, and the animals living in the climbing area are forced out of their places, whenever humans are around. For example, during the summer climbing season, pregnant females of an endangered species of snake live in open areas like roadsides, exposed walls or rocks, where there is less canopy closure compared to areas occupied by non-pregnant females and males. According to climbers, these open areas are very suitable for climbing during summer.

Many rock climbers have understood the significance of wildlife plant and animal preservation and related issues, and therefore take measures to reduce effects on climbing areas. Considering the effect of climbing activities on natural reserves, various national parks and wildlife agencies have put forth certain regulations on climbers. There are seasonal closures of climbing areas to avoid illegal entrance of uninformed rock climbers.

Climbers are always expected to support wilderness preservation. Many environmental organizations have been formed to protect the environment and in the process draw up certain guidelines for rock climbers. Both sides have come to a common understanding of the effect of rock climbers on protected areas.

The food delivery industry now is a hotly competitive business, attracting the world's biggest moneybags such as Amazon, Alibaba and Soft-Bank. Balancing the needs of diners, cooks and couriers（快递员）is complicated. Most new companies lose money. Yet they have received more than $30bn from venture capitalists （投资家）in the past five years. And they are likely to get more.

The food-delivery business can be divided into two camps: mostly profitable veterans（老牌公司）and loss-making newcomers. The veterans, founded at the start of the century, are led by publicly traded Grubhub in America, and Just Eat and Takeaway in Europe. They account for the largest share of the market, offering customers online access to restaurants. Their relatively simple business model, in which they take a cut of the bill from the restaurants, has enabled Grubhub and Just Eat to turn a profit for years. Takeaway makes money in its home market of the Netherlands.

The newbies, born more recently, have turned a once-tidy business into a food fight. For most of them, delivery is their core business, so they share their cut of the bill with riders as well as restaurants. This substantially broadens the market to restaurants but profit suffers.

The only mouthwatering aspect of the delivery business is its potential size. According to Bernstein, a brokerage（经济公司），almost a third of the global restaurant industry is made up of home delivery, takeaway and drive-throughs, which could be worth $l tm by 2023. In 2019 delivery amounted to $161bn, leaving plenty of room for online firms to expand.

Yet it is by no means clear if anyone can make money by delivering meals. In fact, the economics may be even worse. Delivery businesses have ways to cut their losses. One is to diversify further, by delivering groceries, flowers, booze, and even people, as well as meals. Another is to provide cheaper meals by centrally supplying ingredients to restaurants. In the dog — eat — dog world of food delivery, it will still be hard.

Is it time to ditch sugar?

It’s no secret that sugar can cause issues if you’re indulging (放任) in a little too much of the sweet stuff. Still, most Americans are eating too much sugar. The harmful effects it can have on your physical health are well studied.     11    .

Sugar can affect your mood

You probably turn to a doughnut (甜甜圈) or soda for an extra boost during a long day. Yet sugar may not be such a positive pick-me-up after all. Recent research indicates that sugary treats have no positive effect on mood.     12    .

One study published in 2017 found that consuming a diet high in sugar can increase the chances of mood disorders. A more recent 2019 study found that regular consumption of saturated fats (饱和脂肪) and added sugars were related to higher feelings of anxiety in adults over age 60.

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It’s hard to avoid reaching for comfort foods, especially after a difficult day. But the cycle of consuming sugar to manage your emotions may only make your feelings of sadness, tiredness, or hopelessness worse. Multiple studies have found a link between diets high in sugar and depression.

    14    . These can lead to depression and may even increase the long-term risk of developing a mental health disorder in some people.

Sugar destroys your brain power

Emerging research has found that diets high in sugar can damage cognitive functioning, even in the absence of extreme weight gain or too much energy intake. A 2015 study found that consuming high levels of sugar-sweetened drinks made neurocognitive functions like decision making and memory worse.     15    . But a more recent study found that healthy volunteers in their 20s scored worse on memory tests and had poorer appetite control after just 7 days of eating a diet high in saturated fat and added sugars.

Although more studies are needed to solidify the effects on mental health of sugar consumption, it’s important to consider how diet can affect your well-being.