This topic was discussed in a recent version of NAMS Practice Pearl. The most pertinent studies were reviewed by Dr. Krista Varady, PhD, from the University of Illinois at Chicago.
Here is her assessment.
The cause of midlife weight gain is a combination of the following factors: loss of estradiol, age-related decreases in metabolic rate, and for some women, a more sedentary life style. Approximately 40% of women in menopause in the US can be categorized as obese.
There is so much conflicting information about which diet is the most effective for weight loss. It is difficult for physicians, and very confusing for the average women to know which strategy for weight loss has the best scientific data to back up its efficacy. Plus, the metabolism of women at midlife is very different from younger women, and also different than men, so finding studies specific or our sex and age group can be challenging.
Let’s compare low-fat diets to high-protein diets in midlife women:
Three studies of low-fat diets were randomized and controlled, which provides a high level of significance. In the first study, obese women were restricted to <30% fat, and calories were kept between 1200-2000 per day, depending on their weight. After 12 months, the average weight loss was 8.5%. If you started the diet at 180 lbs., you would lose about 15 lbs. in one year. In another study, a very low fat diet, <15% of calories consumed per day, women lost 7.7% of their body weight in 8 months. In another study, where fat was restricted to 20-35%, and calories restricted to a deficit of 500 calories per day, the participants lost 6.1% of their body weight in 4 months, about 11 lbs. for your 180 lb. women.
The Women’s Health Initiative looked at whether a low fat diet was effective in weight maintenance in mid-life women. In this study, more than 19,000 women were asked to restrict their fat intake to <20%, with no limitation in calories for seven years. In the first year, the women lost an average of 1.7%, but maintained about a 1% weight loss for the next seven years, indicating that fat restriction may be a strategy for long term weight maintenance.
Let’s look at the data for high-protein diets.
High-protein diets are effective in preserving muscle mass during weight loss. In one study, a high-protein low-calorie diet was compared to a low protein, low-calories diet, and both compared to an unrestricted diet. Both low calories groups lost the same amount of weight, 10% in six months. Again for our 180 lb. woman, this is 18 lbs. in 6 months. What was most important was that the difference in muscle mass was measured. The high-protein group last half as much muscle as the low-protein group. This is important because our muscle mass determines our resting metabolism: how many calories do you use up when you are at rest, not exercising. If you lose muscle mass, you require less calories to maintain normal functions, and you will need to restrict more to continue losing weight. Two additional studies had similar findings.
The bottom line was that restricted calories, regardless of protein composition of the diet, resulting in similar weight loss. Muscle mass was better preserved with high protein diets, but bone density was not as well preserved, and the benefit of the weight loss on insulin sensitivity was not as good as would have been expected.
Diets that incorporate fasting have become popular. One fasting day alternates with one day of “feasting” The idea is that on fasting days, caloric intake is limited to 500 calories, either at lunch or dinner. On non-fasting days. there is no restriction on what is eaten. Postmenopausal women lost about 11% of their body weight in 6 months with this regime, about 20 lbs. for our 180 lb. woman. Bone density was not affected by the alternative day fasting regime.
So, how do we compare these regimes. Caloric restriction, whether it be low-fat or high protein results in weight loss. High protein seems to be better for maintenance of muscle mass, but possibly sacrificing some loss of bone. What was not discussed was the effect on cholesterol and insulin levels, and the results if these diets were followed in the longer term.
These studies seem to raise many more questions.
Although all studies led to loss of weight, the rate of weight loss was slower than we might hope. For a person who needs to lose more than 20 lbs., it seems that a long-term strategy needs to be used. Rather than dieting, a lifestyle change might be a better approach. Increasing exercise and physical activity gradually can prevent injuries, and finding varied activities that are truly enjoyable may lead to a sustainable program. Incorporating short-term goals that are more easily obtainable may be more effective than going for the 50 lb. weight loss that will take several years to accomplish. Self-monitoring with diet apps that measure the caloric and nutritional value of foods can help to determine if your fat and protein intake are where you want them to be, and to understand the caloric value of portion size and the detriment of snacking and grazing. Many women do well with the structure of programs like Weight Watchers. A nutritionist may be helpful to organize a program individual to your lifestyle and personal preferences.
Unfortunately, long term success with sustained weight loss can be very difficult to obtain.
What is needed is more studies in women after menopause to understand their unique hormone issues how this changes metabolism, and which strategies provide the best success.
Marilyn Jerome, MD
Foxhall OB-Gyn Associates
NAMS Practice Pearl: Dietary Strategies for Weight Loss in Midlife Women, Krista A. Varady, PhD. released December 20, 2017
Two weeks ago I spent two days at the NIH at at a conference on osteoporosis: Pathways to Prevention: Appropriate Use of Drug Therapies to Prevent Osteoporotic Fractures. The goal of the meeting was to bring forward experts and the data to consolidate information regarding recommendations for treatments, understanding risks and side effects of medications, and to better understand gaps in our knowledge. This will hopefully lead to additional research to fill in these gaps.
Because this topic is so broad, I will break it down into smaller topics, and report the information as a series. Let’s start with the burden of the disease, a lecture given by Dr. Elizabeth Shanes.
Osteoporosis is a very significant public health burden. Approximately 10 million Americans have osteoporosis, but most of them do not know it. Osteoporosis is defined as weakness of the bones, resulting in increased risk of fractures. Fractures can lead to surgery, disability, immobility, loss of independence, and decreased life span. As we age, most adults want to maintain their independence and quality of life.
Here are some facts that we know for sure:
There are 1.5-2 million osteoporotic fractures per year in the US, mostly involving the spine, hip, wrist, and pelvis. Women will incur 70% of the burden of these fractures. 50% of women over the age of 50 will sustain at least one fracture in their remaining years. Caucasian women carry the highest risk.
The cause is low bone density which can be measured and monitored. The risk of osteoporosis increases with age. About 44% of women over age 50 have low bone mass. The risk of osteoporosis over age 50 is at least 10%, and may be as much as 30%.
Low bone density predicts fractures, both traumatic fractures as well as low-trauma fractures.As bone density decreases, the risk of fractures increases.
Once you break a bone, you are more likely to break more. If your break a vertebrae, you are 5 times more likely to break another vertebra, and 3 times more likely to break your hip. If you break one vertebrae, you have a 25% chance of breaking another within one year.
Adults who break bones have significant increased morbidity and mortality. After a broken hip, your risk of death in the next three months increases 5-8 times, and the increased mortality remains for the next 10 years. Studies show that other fractures including vertebral, femoral, tibial, multiple rib and other fractures are all associated with increases in mortality. About 25% of women who fracture a hip will live less than a year.
Fractures also decrease mobility. 50% of adults who break a hip will have difficulty walking one year later. Vertebral fractures are related to back pain and difficulty with managing tasks of daily living. Studies show that quality of life decreases after fractures, and the more fractures, the more rapid is the decline. Many people who fracture never regain their quality of life.
The cost to the healthcare system and individuals is dramatic. In 2005 there were 2 million fractures at a cost of 2 billion dollars. One hip fracture costs about $30,000 to treat. As the population ages, the healthcare costs related to fractures will increase. Those who are insured that fracture have twice as high health care costs as those who do not.
Fractures are preventable. All women should be encouraged to take adequate doses of calcium and Vitamin D, and exercise to improve muscle strength and balance. Fall prevention strategies should be discussed with patients. The biggest cause of falls is lack of muscle strength as we age.
Once osteoporosis has been diagnosed, medication is necessary to treat the disease. Many patients will be motivated to increase their calcium, Vitamin D and exercise at that point, but significant improvement in fracture risk is difficult to achieve. Short term use of certain FDA approved medications have been proven to prevent fractures. The long term strategies for drug use need further study.
Medications that prevent fractures are not being effectively. Bisphosphonates (Fosamax, Actonel, Boniva and Reclast) for osteoporosis treatment were approved in the mid-1990’s. Their use increased until about 2008 when media reports surfaced about side effects. The use of these drugs have sharply declined since then, although the risk are very, very rare. The perception by many patients is that the drugs do not work or make the bone more brittle, and the side effects are frequent. This is not true.
Since these reports, physicians have focused on treating those most at risk of fractures, rather than using the drugs preventatively, and have begun using drug holidays when appropriate.
Data indicates that even after hip fractures, less women are being treated for their osteoporosis. Less than 20% of women who break a hip are started on medication to prevent another fracture. New data tells us that for the ten years from 2005-2015, hip fracture rates were decreasing, then stabilized, and are now increasing. There have been about 11,000 more hip fractures and 2300 deaths attributed to the change in the trend. Medicare has markedly lowered reimbursement to doctors for osteoporosis testing in the office, so many practitioners no longer offer this service. The trend in decreased testing and concern of patients over side effects of medication, both contribute to the increase in fractures.
Physicians need to understand the concerns of patients about side effects, and understand the barriers to initiating and continuing treatment, including cost and insurance restrictions. Physicians also need to effectively communicate with patients the devastating effect of fractures, and learn how to prevent and diagnose complications sooner than later.
Here are Dr. Shanes final comments: “Osteoporotic fractures are common, costly, debilitating, disabling, and deadly. Although we have drugs to prevent them, those drugs are not being used.”
We have an opportunity to do better.
The next article in the series will look at who is at risk for a fracture, and who should be screened. We will also talk about how to interpret your results. Stay tuned.
Marilyn Jerome, MD
Foxhall OB-Gyn Associates
NIH: Pathways to Prevention: Osteoporosis
Elizabeth Shane, MD. Osteoporosis Fracture Prevention in the US, October 30, 2018