January, 2007

Worlds Apart — Men, Women, and Their Approach to Weight Loss
By Mary Kaye Sawyer-Morse, PhD, RD, LD
Today’s Dietitian
Vol. 9 No. 1 P. 50

When it comes to losing weight, are men from Mars and women from Venus?

My husband had a birthday recently and did an unexpected thing—he bought a full-length mirror for our bathroom. The following day he announced he needed to lose some weight. No discussion with his wife, the dietitian, was necessary. He researched the local gyms, chose one that offered the programs he preferred, and joined. Next, he entered the exercise schedule into his Palm Pilot. He altered his eating plan: less snack (ie, junk) food and more fruit. No fuss, just a simple, straightforward plan.

His approach to weight loss made me wonder: Do men and women approach and experience weight loss differently?

Physiological Gender Differences
A logical starting point in this weight-loss discussion is to examine potential gender differences in the way fat is accumulated and utilized. Indeed, current research shows that there may be gender differences in the way people store and metabolize fat during rest and exercise. It is well-established that women generally have a higher percentage of body fat than men. A healthy range of body fat for women is 20% to 25%, and a healthy range of body fat for men is 10% to 15%.1

Body fat distribution varies among individuals. Some people carry more of their body fat in and around the abdominal area. This type of fat deposition is called android, or apple body type, and is most characteristic among males. Although some women may also have an apple body type, most are genetically programmed to gain weight in their thighs and buttocks. This body type, called gynoid, or pear shape, is characterized by fat stores in the hip and thigh region. The scientific explanations for the dramatic difference in body fat distribution between men and women are largely unknown, although differences in hormones, hormone receptors, and enzyme concentrations contribute.

If there are gender differences in how fat is deposited, are there also differences in how it is metabolized? The answer appears to be yes.

Fat mobilization refers to the process of releasing fat from storage sites in the body, whereas fat metabolism is the biological breakdown or oxidation of fat into energy the body can utilize. There are two primary enzymes that regulate the mobilization of free fatty acids: hormone sensitive lipase (HSL) and lipoprotein lipase (LPL). HSL is located in the fat cell and is stimulated by the hormone epinephrine. LPL, the second enzyme of lipolysis, is located on blood vessel walls throughout the body. Both adipose tissue and the liver have large quantities of this enzyme.

Epinephrine is the primary hormone that stimulates lipolysis.1 There are two main types of epinephrine receptors: alpha and beta. Epinephrine can stimulate lipolysis through the beta receptors and can inhibit lipolysis through the alpha receptors.2 The type of receptor available and its sensitivity to epinephrine determines the response of HSL in any given tissue.

Here’s where there can be a gender difference: Research has shown that abdominal adipocytes are more sensitive to beta receptor stimulation by epinephrine than hip and thigh adipocytes in both men and women.3 This suggests that fat around the abdominal area may be easier to mobilize than fat located in the hip and thigh areas. In addition, women tend to have a greater number of alpha receptors in the hip and thigh regions, favoring the storage of fat rather than its mobilization.3

A Different Perspective
In addition to physiological differences, there also appears to be psychological differences between men and women regarding weight loss and associated behaviors. One difference is that men often underestimate the degree of their obesity or amount of extra weight and have lower body and weight dissatisfaction than women. This likely explains why men are frequently underrepresented among those seeking weight loss, despite gender similarity in the prevalence of overweight and obesity.4

Another difference is that women, more so than men, are emotional eaters and frequently list overeating triggers such as mood, stress, depression, and low self-esteem. Men, on the other hand, seem to be protected from body dissatisfaction by failing to identify themselves as heavy, even when they are objectively overweight.5 An ability to view oneself as “light” regardless of actual weight may also protect men from developing eating disorders, as this viewpoint is almost the opposite of the body image disturbance experienced by patients with anorexia nervosa.6

An additional gender difference is in the perceived ability to reach set goals. Women score lower than men when estimating their ability to succeed in reaching a specific weight goal. However, women’s scores generally improve during weight loss while men’s scores stay the same.7 In other words, men tend to see themselves as having the ability to reach stated weight goals from the beginning while women experience an increase in self-confidence once they achieve small measures of success.

Physician’s Influence
The physician can be an important factor in the weight-loss equation, whether through prompting weight reduction action or in providing medical support. Although physicians are knowledgeable about the risks associated with obesity, many factors affect the treatment recommendations physicians offer patients. These factors include specific patient attributes such as age, level of motivation, and body mass index (BMI). Treatment recommendations are also influenced by the physician’s own characteristics, with male physicians tending to view patients who are obese as more lacking in self-control than female physicians, and physicians who are overweight being less likely to emphasize the health consequences of obesity to their patients than normal-weight physicians.8 Additionally, physicians are often uncertain about what treatments are most effective and often fail to recommend treatment at all.8

The patient’s gender may also influence the physician’s attitudes and treatment. Anderson et al found that physicians were more likely to encourage women with a BMI of 25 to lose weight than men with the same BMI. While at a significantly higher BMI of 32, physicians more often advise men than women to lose weight.

The reason male patients with the highest BMI are more strongly encouraged to lose weight than female patients is unclear, but it does indicate that physicians may be less likely to encourage weight loss for women who are obese with the same BMI. The physicians are possibly more concerned about the health risks of android body fat distribution in men than women.9

Taking Action and Finding Solutions
Once a man decides to lose weight, what is most likely his next step? Men, more often than women, will exercise rather than substantially change their diet to lose weight.10 Consider my husband’s action plan: join gym, enter exercise plan into Palm Pilot, and make simple changes to diet.

So what does this exercise behavior look like at the gym? Jim Benn and Robbie Celotto are personal trainers at the Fredericksburg (Tex.) Athletic Club. Between them, they have more than 45 years of experience working with clients. As far as the differences they see between men and women and their weight-loss and exercise efforts, they offer numerous observations. Celotto believes a “man oftentimes will hire a personal trainer for one or two sessions and then feel he knows enough to take it from there. A woman, on the other hand, likes to have assistance in developing a plan and guidance in making sure she is following it correctly. She is likely to follow a plan, where[as] a guy will follow a plan for a while and then he’s going to experiment on his own.”

Both Benn and Celotto note that women are typically more open to suggestions from an expert and more likely to ask for help. Men, however, will watch and see what the “biggest guy in the gym is doing and will then try [to] follow his routine.” Benn says a man is more likely to say, “I haven’t worked this body part enough, so I should do twice as much.” Benn also stresses that in working with male clients, he focuses on short-term goals—nothing more than six weeks—to help the client stay interested and challenged. “It’s more of a competition for the guy,” Celotto adds.

Benn and Celotto are quick to say they don’t offer specific nutrition advice—”that’s where a dietitian comes in.” They do, however, offer an interesting observation: “A guy frequently will say, ‘I’ll just work out harder’ rather than adjust his diet. A woman is more likely to realize it’s a balance of both diet and activity.”

“I’d say women are more comfortable with meal preparation and grocery shopping than men. Guys prefer really easy options: meat, potatoes, and pizza,” Benn laughs.

Both trainers emphasize that men benefit from messages that underscore the importance of balanced eating, realistic calorie estimation, and portion control.

To help fill the “healthy food choices with no preparation” need, organized weight-loss companies, such as NutriSystem, are offering specialized programs targeting men. Mary F. Gregg, RD, director of healthcare services for NutriSystem, says men now make up 30% of their participants. And the number is going up. Gregg attributes the program’s popularity among men to its convenience. “The NutriSystem program is easy and anonymous. Men often express a lack of time, and our program is simple to use.”

Gregg, who has been with the company for 17 years, has also observed differences in how men and women approach weight loss. “Men,” she says, “don’t seem to require the same level of psychological and social support as women. They don’t call as much and they seem to eat less out of stress and emotions.”

Interestingly, men tend to stay on the NutriSystem program slightly longer than women—11 weeks vs. nine to 10 weeks, respectively. And are they successful? “Yes,” Gregg responds. “Men typically lose about 2 pounds per week while they are on the NutriSystem program.”

Overall, commercial programs may prove to be valuable resources for men. Research confirms that men will use commercial weight-loss programs when the programs are perceived as easy to access, offer objective, goal-oriented assistance, and limit time involvement.11

It’s an Important Difference
What does all of this mean? There are differences in how men and women approach weight loss. These differences are important to consider in any weight-loss program or plan. Distinguishing which factors play a greater role for either sex is important to ensure successful and sustainable weight loss.

— Mary Kaye Sawyer-Morse, PhD, RD, LD, is a professional speaker, an author, and a wellness expert. She is the owner and education director of The Center for Success, a Texas-based company that provides keynotes, in-service training, and seminars to diverse industries.


References
1. Rasmussen BB, Wolfe RR. Regulation of fatty acid oxidation in skeletal muscle. Annu Rev Nutr. 1999;19:463-484.

2. Blair SN, Mzhaman MZ. The public health problem of increasing prevalence rates of obesity and what should be done about it. Mayo Clin Proc. 2002;77(2):109-113.

3. Blaak E. Gender differences in fat metabolism. Curr Opin Clin Nutr Metab Care. 2001;4(6):499-502.

4. Leit RA, Pope HG Jr, Gray JJ. Cultural expectations of muscularity in men: The evolution of playgirl centerfolds. Int J Eat Disord. 2000;29(1):90-93.

5. Miller CT, Downey KT. A meta-analysis of heavyweight and self-esteem. Pers Soc Psychol Rev. 1999;3(1):68-84.

6. Cohane GH, Pope HG Jr. Body image in boys: A review of the literature. Int J Eat Disord. 2001;29(4):373-379.

7. Tiggemann M, Rothblum ED. Gender differences in internal beliefs about weight and negative attitudes towards self and others. Psychol Women Q. 1997;21(4):497-662.

8. Sciamanna CN, Tate DF, Lang W, et al. Who reports receiving advice to lose weight? Results from a multistate survey. Arch Intern Med. 2000;160(15):2334-2339.

9. Anderson C, Peterson CB, Fletcher L, et al. Weight loss and gender: An examination of physician attitudes. Obes Res. 2001;9(4):257-263.

10. Bish CL, Blanck HM, Serdula MK, et al. Diet and physical activity behaviors among Americans trying to lose weight: 2000 Behavioral Risk Factor Surveillance System. Obes Res. 2005;13(3):596-607.

11. Bye C, Avery A, Lavin J. Tackling obesity in men—preliminary evaluation of men-only groups within a commercial slimming organization. J Hum Nutr Diet. 2005;18(5):391-394.