Dear Readers, this will be my 250th column over the past two years. Writing for you has been a great opportunity, and I thank all of you for the questions you have given me. In trying to convey the best information possible, I have learned a great deal. I have pored through multiple articles in my attempt to glean the truth buried within the scientific evidence and to explain how it applies to our everyday life. Now, however, other duties beckon, and so this is my last article for you. My colleagues, Dr. Eve Glazier and Dr. Elizabeth Ko, will continue writing the column and addressing your medical queries.

I feel both a sense of satisfaction in helping so many people, as well as a great deal of regret that I may not have the frequent opportunity to unearth what remains a wealth of untapped knowledge.

There remains a great deal of confusion and much misinformation about health and disease. Even I cling to notions that may be incorrect and, when confronted with studies that are contrary to my beliefs, I must overcome my hubris and admit when I'm wrong. It would be nice if we could all do that.

In one last salvo, I would like to give you my hope for a healthier society:

-- A healthy society is one that provides access to vegetables, fruits and animal protein and rejects the multiple processed foods and desserts that have flooded our markets.

-- A healthy society is one that decreases pollutants that contaminate the air we breathe and the water we drink.

-- A healthy society should have open spaces for its people to hike, walk, saunter or just sit reading a book or taking time to watch the sun set.

-- A healthy society has compassion for its individual members and a reverence to the Earth that harbors them.

I hope that my efforts have provided insight and guidance about your health, even as I hope that each person can commit to contributing in some way to make our world a better place.

To do that, each of us has to take responsibility for our own health. Succumbing to the plethora of unhealthy foods, drugs, alcohol and tobacco available to us, or using one's nonwork time glued to some form of visual entertainment, will not make a healthy individual. Instead, poor health habits lead to disease, the taking of multiple medications with side effects and the inability to live life fully. Our consumer industries feed off our unhealthy habits and, in concordance, our health care becomes ever more expensive. These choices are up to us.

I'd like to thank my wife and kids for being patient with me while I worked on these articles on the weekends. As for me, my first weekend endeavor will be to clean up my garage. It's a mess. I will continue to write medical articles for UCLA Health and will be promoting my novel, "Beautifully Absurd." And I will continue my work as a primary care physician, where I will continue to learn about medicine and the everyday lives of human existence. Thank you.

(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: I just read that some parts of the medical community may finally be taking the idea of fecal transplants seriously. What are the latest advances? And what's taking so long?

Dear Reader: We think you may be referring to a study about fecal transplants that made quite a few headlines when the results were published in the New England Journal of Medicine in June. Researchers from Norway assessed the efficacy of various treatments on patients with a dangerous and potentially deadly intestinal infection caused by a type of bacteria called Clostridium difficile, also referred to as C. diff. The bacterium causes symptoms that include frequent diarrhea, high fever, nausea and dehydration that can adversely affect heart rate, blood pressure, kidney function and overall health. In the most severe cases, C. diff causes a type of inflammation of the colon that can lead to death.

In the study, 20 patients with C. diff infections were randomly assigned to either undergo standard treatment with antibiotics or to receive a fecal transplant. For those unfamiliar with the concept, that's the process by which specially prepared stool from a healthy individual is transferred into the colon of the sick person. The idea is that the "good" bacteria from the healthy individual will populate the colon of the patient and vanquish the C. diff bacteria. People who donate stool for a fecal transplant undergo extensive testing be sure no pathogens, such as bacteria, fungi, viruses or parasites, get transferred to the recipient.

Of the nine C. diff. patients in the study who received the fecal transplant, five were cured immediately. Five of the 11 patients who received antibiotics were also cured. In this particular study, fecal transplants were shown to be as effective as antibiotics for the treatment of C. diff. In a time of increasing antibiotic resistance, this is an important development. However, the study, with just 20 patients, is too small to use to draw definitive conclusions. The researchers have announced plans to repeat their work with 200 patients in the near future.

As to why progress in the arena of fecal transplants appears to be slow, we think it's a combination of things. Any new approaches in medicine have to undergo comprehensive testing, studies and clinical trials to be sure that they are safe, and to fine-tune the specifics of treatments, dosage and procedures. Compared to how quickly information gets shared these days, the bench-to-bedside process may appear to move at a glacial pace. It's also true that new ideas can face resistance in the medical community. We're thinking of how, in the early 1980s, the idea that peptic ulcers and gastric cancers were caused by certain bacteria was thought to be ludicrous. Two decades later, though, the Australian doctor who came up with the theory, which was eventually proven to be correct, won the Nobel Prize.

At this time, although fecal transplants are permitted by the FDA, they are to be used only when treatment with antibiotics has failed. This new study, despite its small size, may offer a persuasive argument for more extensive research with an eye toward revisiting treatment priorities.

(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: I recently saw a TV show in which a physician said sweets cause dementia. Is this true? As a sweet-aholic, I hope not.

Dear Reader: How I used to love sugar as a child. My parents didn't have many sugary foods in the house, so I would gorge on sweets at my friends' houses or when the ice cream man made his rounds. At age 11, however, I began to understand the health consequences of sucrose -- I knew that it increased the risk of diabetes and was directly connected to weight gain. I learned much later about the less tangible dangers -- metabolic changes, heart disease risk and a potential link to cancer.

Many people, however, continue to indulge in sweets well into old age. While some can do so with relative control, others cannot. The problem for everyone is that, as we grow older, our ability to process sugars declines, leading to an increased risk of obesity and diabetes, among other things.

The dementia connection has to do with how our brains receive nutrients and oxygen. While many large blood vessels supply blood flow to the brain, equally important are the small blood vessels that nourish the neurons. Small blood vessels are quite susceptible to injury, especially those caused by high blood pressure and diabetes. That's why people with poorly controlled diabetes are at risk for slow-to-heal ulcerations: The small vessel disease in the lower legs leads to poor blood flow and nerve dysfunction. Similarly, poorly controlled diabetes can also lead to small blood vessel disease in the brain and the death of neurons. Multiple epidemiologic studies have shown a correlation between diabetes and dementia, as have MRI studies in animals.

I'm sorry to add that, even if you're a sweet-aholic who doesn't have diabetes, you may be at risk too. A review of eight studies in Japan assessed the levels of hemoglobin A1c, a marker for diabetes, and the rate of dementia within the general Japanese population. The authors found a concordance between an increased rate of elevated hemoglobin A1c and increased rates of dementia.

Increased memory impairments were even correlated with hemoglobin A1c levels greater than 6, which does not meet the threshold for diabetes. This may be related to increased production of insulin in people with higher intakes of sugar and carbohydrates, which subsequently leads to insulin resistance. Insulin resistance, in turn, may lead to a difficulty in the ability of neurons to transmit information to one another.

Of course, eating sweets also increases the likelihood of obesity, and midlife obesity itself has been correlated with dementia. There are many theories as to why this is the case, including that fat cells secrete brain-damaging inflammatory compounds or that fat cells store dangerous pesticides from the environment. What appears more likely is that obesity increases the risk of hypertension and sleep apnea, both of which increase the risk of dementia.

I understand that sweets bring pleasure and that telling people they shouldn't eat them seems cruel, but when you look at how much damage sweets create in both the body and mind, as a doctor, I find it difficult to condone their consumption. Consider that Native American populations have been ravaged by diabetes and poor health related to sweets, which were never traditionally part of their diet -- and this is a lesson all of us ignore at our peril.

Kicking this addiction will lead to improved physical and mental health and lower your risk for dementia. I know you can do it.

(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.)