Dear Doctor: I have some dark chocolate every day and my (otherwise kind and loving) husband teases me for believing the news stories that chocolate is good for you. Please tell me that I haven't fallen for a bunch of quack science!

Dear Doctor: We can certainly understand how the idea that chocolate offers health benefits might spark a bit of skepticism. After all, when we hear about so-called superfoods, it's foods like kale, fish oil or green tea that tend to top the list. The idea that something as delicious as chocolate might be anything more than an indulgence takes a bit of getting used to. And yet you're right -- a number of studies have linked chocolate with a range of positive outcomes. The results of recent research suggest that chocolate improves memory and brain function, lowers blood pressure and cholesterol, can boost immunity and has a positive effect on mood.

But before you unwrap a chocolate bar in celebration, there's an important caveat. It's only dark chocolate that confers these positive effects. That is, chocolate with a minimum cacao concentration of 70 percent. That's because cacao is rich in chemical substances known as flavanols, which have potent antioxidant properties. Studies have shown that flavanols have a positive effect on connections between brain cells, offer protection from toxins and can shield the body from some of the damaging effects of inflammation.

The catch here is that in its pure state, cacao is relentlessly bitter. It's the sugar and fat that get added during manufacturing that give chocolate its sweetness and silky-smooth feel. For many people, the high levels of cacao needed for chocolate to become potentially beneficial render it unpalatable. If you're a lover of dark chocolate, though, you're in luck.

The results of two recent studies regarding dark chocolate, which were presented at the Experimental Biology 2018 annual meeting last April, back up many of the existing health claims about dark chocolate. (They also give you some recent data to use the next time you get teased for your chocolate-loving ways.) Researchers from Loma Linda University examined the brain scans of study participants before and after they ate 48 grams -- that's 1.7 ounces -- of dark chocolate. In the post-chocolate scans, they saw increased activity among certain immune cells in functions like T-cell activation, cellular immune response and in genes involved in neural signaling. That translates to beneficial effects on mood, memory, stress levels and inflammation. As with all studies that have a fairly small sample size, the findings here need further investigation to nail down the cause-and-effect of what the researchers saw.

Meanwhile, when you do eat chocolate, be sure to go for 70 percent cacao or higher. Natural chocolate has more flavanols than Dutch process, which uses alkali to neutralize the acid found in cacao. This makes it tastier, but also lowers the flavanol content. And remember that despite all of its potential health benefits, chocolate is also delivering both fat and calories. Be sure to adjust your diet accordingly.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctor: Is it true that just cutting back on refined sugar, refined grains and highly processed foods can lead to weight loss without cutting calories? If so, count me in. But I could eat a whole lot of whole grains and vegetables before being satisfied. That's still a lot of calories.

Dear Reader: Based on the specifics, we think you're referring to the results of a clinical trial published earlier this year in the Journal of the American Medical Association. The takeaway from the research itself is extremely interesting, but equally fascinating has been how the results have been interpreted in the media. Much of the coverage trumpeted the idea that (at last!) here's a diet where you lose weight without counting calories. And though it's true that caloric restrictions were not built into the study, among the findings was that participants wound up consuming an average of about 500 fewer calories per day.

A team of researchers working in partnership with the National Institutes of Health studied 600 overweight people over the course of a year as they followed eating programs consisting of only high-quality whole foods and beverages. That means heavy on fruits, vegetables, lean proteins, healthful fats, and whole grains and legumes, and few or no highly processed foods. Not only are those loaded with salt, fat, sugars and highly refined carbohydrates, but they've been repeatedly linked to obesity, diabetes, cardiovascular disease and various cancers.

The actual point of the study was whether an individual's genetic makeup or insulin metabolism can predict weight loss or health outcomes. To that end, the study participants were randomly assigned to a diet that was either low in fat, or one that was low in carbs. Over the course of the year the people in the study, all of whom were overweight, also attended 22 counseling sessions with a dietitian.

Just so you know, the conclusion was that genotype and insulin production didn't appear to be predictors of weight loss in either group. Also, neither diet appeared to be superior for weight loss. But what got the most ink was that so many participants lost weight without counting calories. Low-carb participants lost an average of 13 pounds each, while the low-fat group lost an average of 11.7 pounds each. A few people dropped significant weight -- up to 60 pounds -- and some gained weight. And both groups saw drops in waistline measurements, body fat percentage, blood pressure, and fasting levels of insulin and glucose.

So what happened? It appears that by quitting junk foods in favor of a diet of high-quality whole foods, people in the study naturally ate fewer calories without trying to cut back. The fact that all of those health markers also moved in a positive direction speaks volumes for the benefits of this type of eating. What strikes us is that, for all the diets and eating plans and food hacks that have emerged over the decades (centuries, really), it always comes back to the basics -- a balanced diet of whole foods, lean meats, good oils, and plenty of fresh fruit and vegetables.

Now, please, go eat an apple.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctor: It seems as if people, without fail, say they feel better when the sun is shining, yet the medical community seems to tell people to stay away from the sun. The sun is shining as I ask: Is there some conspiracy here?

Dear Reader: We wouldn't say there's a conspiracy afoot when it comes to advice regarding the sun and sunshine, but there certainly are plenty of inconsistencies. On one hand, there's the indisputable link between exposure to the sun's rays and a range of skin cancers. On the other hand, there are all of the ways that the availability of sunlight is tied not only to mood, but to metabolism as well. When taken together, the various warnings and admonitions about getting too much or too little sunlight and sunshine add up to a snarl of contradictions.

On the "less sun" side of the equation are the physical changes that exposure to sunlight can cause to the skin. In the short-term, there's tanning, which in our culture is associated with health and well-being. However, the physiological changes that cause the skin to get that sun-kissed glow are actually signaling that damage is taking place at a cellular level. Many of the signs of aging, including wrinkles, dark spots, splotches and sagging, are due to sun exposure. Ultraviolet light, a specific spectrum in the sun's rays, damages fibers in the skin known as elastin. These are a key component in keeping your skin taut, flexible and youthful. Of even greater concern is the fact that sun exposure raises the risk of a variety of skin cancers, some of them aggressive and potentially fatal.

But you're right -- sunlight is crucial to our emotional and physical well-being. Our circadian clocks, which oversee functions like sleep-wake cycles, mood, appetite, energy levels and hormone production, rely on the rhythms of the sun to stay in sync. Vitamin D, known as the "sunshine vitamin," is manufactured by the body through a process that is triggered by sunlight on the skin. We know that you need vitamin D to build bone. But the fact that many of the tissues and organs in the body have vitamin D receptors suggests it's important to other physiological functions as well.

So what's the sweet spot when it comes to getting enough sun, but not too much? If you're not getting adequate vitamin D from supplements or fortified food, spend 15 to 30 minutes per day in direct sunlight. And because sunscreen has been found to block 90 percent of vitamin D production, leave your skin unprotected for that time. (But be sure to put on the sunscreen and cover up with long sleeves and a hat once the vitamin D time is over.)

When it comes to mental well-being, years of research show that spending time outdoors is good for us. Sunlight plays a role, and so does the length of available daylight. We agree with you that it's important to take the time each day to get out of the house or workplace and spend some time outside.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)