Using Portion-Controlled Ready Meals for Weight Loss

As obesity rates continue to climb, bigger portion sizes over the last few decades have been identified as a potential culprit 1. Strategies to keep portion control in could help people lose weight. A new study published in the journal Obesity suggests that prepackaged, portion-controlled meals can be an effective tool for weight loss 2.

In the study, 183 individuals were randomized to one of three diet groups for 3 months. One group was provided with two prepackaged, portion-controlled meals daily, one group was provided with two prepackaged, portion-controlled meals high in protein (at least 25% of calories came from protein), and one group chose all their meals. All groups had a counseling session with a registered dietitian where they talked about eating a lower calorie diet and were instructed to do at least 60 minutes of purposeful, physical activity per day.Cardel Randomization Slide of portion control paperAt the end of the 3 months, the individuals who ate two prepackaged meals daily lost about 8 percent of their initial body weight compared with the group who chose their own meals who lost about 6.0% of their body weight. Those who ate the prepackaged meals were also more likely to lower their LDL cholesterol (“bad cholesterol”) and triglycerides. There were no differences in food and meal satisfaction between the groups. This is important because if people aren’t happy with a meal plan, they aren’t going to stick to it for long. A limitation of the study is that it was completed during a fairly short time period of 3 months and longer studies are needed to see if prepackaged meals continue to be effective for weight loss after a 3 month period.

Cardel Good Day Orlando
Discussing this topic on Fox 35 News Orlando

Based on these study results, it appears that eating prepackaged, portion-controlled meals can be an effective strategy for weight loss. This may be because it eliminates the need for the planning and preparation of healthy meals that some people find challenging to fit into their schedule. Admittedly, I have never been one to consume prepackaged, portion-controlled meals regularly. However, I have observed that they can be helpful for some patients I have counseled for weight loss. Long gone are the days where a prepackaged, portion-controlled meal equates to the image of the old school TV dinners. Today, there are a variety of companies that specialize in prepackaged meals and consumers can find lower sodium, organic, gluten- and allergen-free, and ethnic options. Some things you may want to look for when selecting prepackaged, portion-controlled foods are described below.

Guidelines for selecting prepackaged, portion-controlled meals:

  • A high sodium content is a common offender in many prepackaged foods. The Dietary Guidelines for Americans recommends no more than 2,300 mg of sodium daily for the average healthy adult and no more than 1,500 mg of sodium daily for those who are salt sensitive or who have been put on a low sodium diet by their physician. Select items with no more than 600 mg of sodium.
  • If your goal is to lose weight, select a meal with less than 500 calories.
  • Avoid products that use trans Make sure to read the ingredient list and if you see “partially hydrogenated oil” for example, then the product includes trans fat and is not an ideal choice.


  1. Piernas C and Popkin BM. Increased portion sizes from energy-dense foods affect total energy intake at eating occasions in US children and adolescents: patterns and trends by age group and sociodemographic characteristics, 1977–2006. The American Journal of Clinical Nutrition. 2011;94:1324-1332.
  2. Rock CL, Flatt SW, Pakiz B, Barkai H-S, Heath DD and Krumhar KC. Randomized clinical trial of portion-controlled prepackaged foods to promote weight loss. Obesity. 2016;24:1230-1237.

New CDC Reports Show Obesity Rates Continue to Climb: How Can We Make it Stop

As an obesity and nutrition scientist, I was disappointed to see the latest reports of obesity prevalence in the U.S. in adults 1 and youth 2 in The Journal of the American Medical Association. The news from the Centers for Disease Control and Prevention is not good, but nor is it surprising, and it is clear that all efforts (including mine) to put a stop to the obesity epidemic are having little effect. Overall, the studies show that 38 percent of adults 1 and 17 percent  of children and adolescents 2 in the U.S. are medically defined as obese. People with obesity are more likely to have type 2 diabetes, heart disease, Alzheimer’s disease, and even some cancers (including endometrium, breast, kidney, colorectal, pancreas, esophagus, ovaries, gallbladder, thyroid, and possibly prostate).

obesity medical

The study in adults 1 looked at datafrom 2013-2014 in 5,455 adults who participated in a national survey. The results were grim – more than 1 in 3 men are obese (medically defined as having a body mass index (BMI) greater than 30), with 5.5 percent considered morbidly obese (BMI greater than 40). In women, over 40 percent are obese and almost 10 percent are morbidly obese. These numbers have not changed much since 2005 in men but have increased slightly in women. Individuals with education beyond high school, non-Hispanic whites and Asians, and 20-39 year olds were significantly less likely to be obese.

The study in youth 2 included data on 7,017 children and adolescents from 2011-2014. 17 percent of kids are obese (medically defined as a BMI higher than the 95th percentile of kids the same age and sex) and 5.8 percent have extreme obesity (medically defined as a BMI higher than the 120th percentile of kids the same age and sex). When broken down by age group, 8.9 percent of 2-5 year olds are obese and 1.7 percent has extreme obesity. In 6-11 year olds, 17.5 percent are obese and 5.6 percent have severe obesity. In teenagers (12-19 year olds), the numbers were the most worrisome with one in five considered to be obese and 7.8 percent with extreme obesity.

There has been a great deal of support from The White House, government agencies, foundations, professional organizations, and industries to conduct research, implement prevention and intervention programs, and to create new drugs and devices. Communities, advocacy groups, schools, insurance programs, and foundations have fought to change food policy guidelines and have come together in an attempt to increase physical activity as well as access and consumption of healthy foods. In all likelihood, the obesity epidemic would be much worse without these collaborative efforts (though it is impossible to really know). As proud as I am of all of these entities coming together, the scientifically important work that my colleagues from across the globe have been conducting, and the steps that I have attempted to take to combat the obesity epidemic, the numbers reported here do not show much success.

When I start to get discouraged, I try to think about the global fight against tobacco and the decades upon decades of work, education, and advocacy that were accomplished, and how it eventually took changing social norms for real change to occur. Though tobacco use is very different from the complexities of obesity that are a result of genetic, environmental, and behavioral factors, it is time to really start thinking out of the box and trying a different approach to obesity prevention and treatment using previously successful models of change (i.e., tobacco, recycling, seat belt use) as inspiration. Perhaps it is also time for our society to stop blaming the food and restaurant industries for our obesogenic environment and bring together interdisciplinary teams of scientists, the medical community, public health officials, and the food industry to start working on ways to put a stop to the obesity epidemic.


  1. Flegal KM, Kruszon-Moran D, Carroll MD, Fryar CD and Ogden CL. Trends in obesity among adults in the united states, 2005 to 2014. JAMA. 2016;315:2284-2291.
  2. Ogden CL, Carroll MD, Lawman HG and et al. Trends in obesity prevalence among children and adolescents in the united states, 1988-1994 through 2013-2014. JAMA. 2016;315:2292-2299.


Is Exercise Enough?

With rising obesity rates across the country, there has been a strong push from health providers and policy makers to promote healthy nutritional habits and to increase participation in exercise programs. Although nutrition remains essential for weight loss, exercising is also important to balance energy. Being active not only increases metabolism, but also decreases the risks of cardiovascular diseases and type 2 diabetes. There is even some preliminary evidence that being physically active may limit the cognitive impairment that is part of the aging process.

The World Health Organization (WHO) and the Center for Disease Control and Prevention (CDC) recommend 150 minutes per week of moderate to vigorous physical activity for adults, and 60 minutes per day for children and young adults. However, most people in the western world are fairly sedentary, meaning that they aren’t getting the recommended amount of physical activity and they spend a lot of time sitting. This raises the question: can a little bit of exercise counteract the negative effects of a sedentary lifestyle? And if so, what amount is sufficient? Of course, if you are a professional cyclist, racing 120 days per year, how much time you sit at home matters very little. But if you are an office employee, sitting 40 hrs a week in an office, it isn’t clear whether 150 minutes of physical activity is sufficient to stay healthy.

A study done in the United Kingdom by Edwardson et al. tried to answer this question and evaluated the impact of physical activity and lifestyle by comparing 4 types of people: ‘busy bees’ (physically active and low sedentary), ‘sedentary exercisers’ (physically active and high sedentary), ‘light movers’ (physically inactive and low sedentary), and ‘couch potatoes’ (physically inactive and high sedentary). The cut-off to be defined as physically active is set to 150 minutes of moderate to vigorous physical activity a week. Their results suggest that physical activity, at least in part, can cancel out some of the negative effects of a sedentary lifestyle. Additionally, people who were physically active had a better heart healthy profile (including lower Body Mass Index, waist circumference, indicators of inflammation, etc.) regardless of how sedentary they were during the day. On the other hand, less time sitting was associated with better HDL (the good cholesterol).

Other studies have shown clear benefits of being physically active, including a longer lifespan and a higher quality of life. The work by Ortega et al. indicates that individuals with obesity but good cardiorespiratory fitness are more likely to have higher quality of life and a longer life when compared to individuals who are normal weight but have poor cardiorespiratory fitness.

Florida Sunday Spin. Courtesy: Tic Bowen

So, don’t wait any longer to start exercising! Find activities you enjoy doing, set goals, keep things simple, and be consistent.



Association of mutually exclusive categories of physical activity and sedentary time with markers of cardiometabolic health in English adults: a cross-sectional analysis of the Health Survey for England. Bakrania K. et al. BMC Public Health, 2016; 16:25.

Long-term health benefits of physical activity – a systematic review of longitudinal studies. Reiner M. et al. BMC Public Health, 2013; 13:813.

The intriguing metabolically healthy but obese phenotype: cardiovascular prognosis and role of fitness. Ortega F. et al. European Heart Journal, 2012.

Sedentary behavior and health outcomes: an overview of systematic reviews. de Rezende LFM. et al. PLOS One 2014.