So-called low fat foods can contain a similar number of calories as the standard versions - and might have more sugar, according to a study.

Which? found six out of 10 consumers eat low-fat and light foods several times a week thinking they are a healthier option. But a "snapshot sample" of 12 low-fat, reduced and light products compared with their standard counterparts found some minimal differences in calorie content, the consumer watchdog said.

A standard McVitie's chocolate digestive contained 85 calories and a light one had 77. The difference of eight calories could be burned off in less than a minute of swimming or running.

A Tesco low-fat yoghurt had more calories per pot at 130 than a standard Activia version at 123, while the Tesco option contained more sugar at 20.2g - more than four teaspoons - than the 16.9g in the Activia pot. The high fat and saturated fat content of cheese meant Cathedral City lighter cheddar was still rated red under the traffic light labeling system.

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  • Serving Size

    "The entire food label is based on one thing, and that's serving size," Blatner says. "It is the most underestimated, under-written about, under-talked about thing on a food label." And so, accordingly, this should be the first thing you look at when scanning the back of a package. Planning to eat all three servings in a bag of pretzels? You'll need to remember to multiply all the numbers below by three. Learn more about <a href="http://www.huffingtonpost.com/2012/08/23/serving-sizes_n_1822551.html?utm_hp_ref=health-problems" target="_hplink">how serving sizes are determined here</a>.

  • Calories (And Calories From Fat)

    Now that two thirds of the U.S. population is overweight or obese, Blatner says calories should be your next stop when evaluating a label. "Calories make the world go round with weight," she says. Forty calories per serving is considered "low," 100 calories is "moderate" and 400 calories and beyond is "high," <a href="http://www.heart.org/HEARTORG/GettingHealthy/NutritionCenter/HeartSmartShopping/Reading-Food-Nutrition-Labels_UCM_300132_Article.jsp" target="_hplink">according to the American Heart Association</a>. Food labels are based on a 2,000 calorie diet -- you might need more or less depending on your age, weight, gender and activity level. For reference, calculate your recommended daily calorie intake <a href="http://www.mayoclinic.com/health/calorie-calculator/NU00598" target="_hplink">by clicking over to the Mayo Clinic</a>, and speak to your doctor for specific recommendations. As for that "calories from fat" line? Skip it, Smithson says. "It's confusing and it doesn't give as much great information as the other parts of the label."

  • Fat (Total Fat, Saturated Fat, Trans Fat)

    In the past, Blatner says, people obsessed about the "total fat" line on the label -- but now we know there are actually <em>good</em> fats we need in our diet, namely the heart-healthy monounsaturated and polyunsaturated fats (found, for instance, in fatty fish). So instead of focusing on the total fat count, look for saturated fats, which raise blood cholesterol levels and increase risk for heart disease and stroke. <a href="http://www.heart.org/HEARTORG/GettingHealthy/FatsAndOils/Fats101/Saturated-Fats_UCM_301110_Article.jsp" target="_hplink">The American Heart Association recommends</a> limiting these fats to 7 percent of total daily calories -- that adds up to 16 grams for someone on a 2,000 calorie-a-day diet. Too complicated? Try the 5 and 20 trick: 5 percent of your daily value is considered low and 20 percent is considered high, anything in between is moderate. So aim for 5 percent or less on the things you don't want (like saturated fat) and 20 percent or more on the things you do. Trans fats are especially dangerous, as they raise your LDL (bad) cholesterol and lower your good (HDL) cholesterol at the same time, <a href="http://www.mayoclinic.com/health/trans-fat/CL00032" target="_hplink">according to the Mayo Clinic</a>. Fortunately, many manufacturers have scrambled to remove trans fat from their products. But Smithson points out that a label can say it has 0 g of trans fat as long as it actually contains .49 grams or fewer -- meaning that if you consume more than one serving size, you might still go beyond the daily limits. Look for the words "partially hydrogenated" on the ingredient label, which is another way of saying trans fat, <a href="http://www.mayoclinic.com/health/trans-fat/CL00032 " target="_hplink">the Mayo Clinic says</a>.

  • Cholesterol

    "Saturated fat is tied even more to your actual body cholesterol levels than cholesterol in food itself," Blatner says, so when doing a quick label scan, you're better off to look for the former rather than the latter. That said, you should still keep the amount of cholesterol as low as possible (5 percent of your daily value or less according to the 5 and 20 rule). And remember that cholesterol only occurs in animal products -- if a bag of peanuts, for instance, is boasting being "cholesterol free," that's no great feat.

  • Sodium

    The average sodium intake among Americans is 3,436 mg a day, <a href="http://www.cdc.gov/features/dssodium/" target="_hplink">according to the CDC</a>, more than 1,000 milligrams above the recommended upper limit of 2,300 mg for the general population. And too much sodium can increase blood pressure and, in turn, risk for heart disease and stroke. Sodium is one stop you'll definitely want to make on the food label, Blatner says. While you might be able to spot a calorie-rich or a carb-heavy food in the store, it can be surprising how many foods contain salt (<a href="http://www.huffingtonpost.com/2012/07/20/how-much-salt-is-in-cereal-cake-ketchup_n_1687403.html" target="_hplink">breakfast cereal anyone?</a>) The 5 and 20 rule definitely applies here -- aim for foods that have 5 or fewer percent of your daily value of sodium. But Smithson points out that those percentages are only based on the 2,300 mg recommended for the <em>general</em> population -- people over age 51, African Americans, and those with high blood pressure, diabetes and chronic kidney disease should curb their intake to 1,500 mg of sodium a day. In fact, those "special populations" <a href="http://www.cdc.gov/features/dssodium/" target="_hplink">add up to the majority of adults</a>, according to the CDC -- and that means you'll need to calculate your own daily values at the store.

  • Total Carb

    Despite their bad rap, carbs are an important nutrient, and a key source of energy for the body. (Complex carbohydrates, which include whole grains, are the healthier pick over refined or simple carbohydrates, <a href="http://www.nlm.nih.gov/medlineplus/carbohydrates.html" target="_hplink">according to the NIH</a>). Carb counting <em>is</em> important for people with diabetes, Smithson explains, as <a href="http://www.diabetes.org/food-and-fitness/food/what-can-i-eat/carbohydrates.html" target="_hplink">carbohydrates raise blood glucose levels</a>.

  • Fiber

    Plenty of dietary fiber is important for maintaining intestinal regularity and bowel health, Smithson explains. Other benefits include reducing blood cholesterol levels and controlling blood sugar levels, and assisting in weight loss, <a href="http://www.mayoclinic.com/health/fiber/NU00033" target="_hplink">according to the Mayo Clinic</a>. <a href="http://www.choosemyplate.gov/faqs.html" target="_hplink">The USDA recommends consuming 14 g of fiber</a> for every 1,000 calories per day, which adds up to 28 g for someone on a 2,000 calorie diet. But no need to do math -- the 5 and 20 rule applies again; shoot to pick foods with 20 percent or more of your daily value of fiber. For a list of surprisingly rich sources of fiber, <a href="http://www.huffingtonpost.com/2012/05/29/high-fiber-foods_n_1543165.html" target="_hplink">click here</a>.

  • Sugars

    <a href="http://www.fda.gov/Food/ResourcesForYou/Consumers/NFLPM/ucm274593.htm" target="_hplink">According to the FDA</a>, there's no percent daily value next to sugar, as no recommendations have been made at this point for how much to eat in a day. But the American Heart Association recommends keeping added sugar consumption to 6 teaspoons a day for women and 9 teaspoons for men. The reality is that the average American is consuming more than <em>22</em> teaspoons a day. So without a percent daily value, you'll have to do a little math on this one. According to WebMD, <a href="http://www.webmd.com/food-recipes/features/sugar-shockers-foods-surprisingly-high-in-sugar" target="_hplink">each teaspoon of sugar is about 4 g</a>. So that means women should keep daily sugar intake at 24 g or fewer a day, and men should stay at 36 g or fewer. But there is a difference between natural occurring sugars, which can be found in foods like fruits and milk, and added sugars. Unfortunately the labels don't divide up the two, so Smithson suggests doing a little sleuthing on the ingredient label to look for sugar (or sugar synonyms, such as high fructose corn syrup, maltose or dextrose -- <a href="http://www.huffingtonpost.com/2012/09/13/other-names-for-sugar-maltose-dextrose_n_1874487.html " target="_hplink">check out our complete list of sugar disguises here</a>).

  • Protein

    <a href="http://www.cdc.gov/nutrition/everyone/basics/protein.html" target="_hplink">According to the CDC</a>, about 35 percent of your daily calories should come from protein -- that's about 46 g for adult women and 56 g for adult men. <a href="http://www.fda.gov/Food/ResourcesForYou/Consumers/NFLPM/ucm274593.htm" target="_hplink">The FDA doesn't require labels to list percent daily values</a> for protein (unless a claim is made that it's "high protein"), as most adults and children consume plenty of the nutrient. Meat may be the most well-known source of protein, but it's definitely not the only option -- for a list of meat-free sources, <a href="http://www.huffingtonpost.com/2012/05/24/vegetarian-protein-sources_n_1539928.html" target="_hplink">click here</a>.

  • Vitamins

    Here comes the good end of the 5 and 20 rule -- aim to choose foods that have 20 percent or more of Vitamin A, Vitamin C, Calcium or iron, as that means they're a good source of the nutrient. Remember that foods within the same category can have widely varying amounts of each vitamin, making comparisons particularly important. Yogurt, for instance, might have anywhere from 15 to 45 percent of your daily calcium requirement, Smithson explains. These nutrients are only expressed in percent daily values on nutrition labels -- aim to get each one to add up to 100 percent. If you're watching calcium intake, you can calculate mg (women under 50 need 1,000 mg a day and women over 50 need 1,200 mg a day for bone health) by adding a 0 to the end of the percent daily value, Smithson says. If something has, say 15 percent of your daily calcium, that calculates out to 150 mg. Some ingredient labels also mention B vitamins, such as riboflavin and thiamin, which she says are less of a concern, as we typically don't have shortages in these. Come to think of it, we've never seen a label brag that it's a "good source of thiamin."

Which? found misconceptions among consumers about the meaning of the terms reduced fat and light, with 16% of people correctly responding that products carrying the label had to contain 30% less fat than the standard alternative.

Labelling regulations define low fat as containing less than 3% fat, the terms reduced fat, light and lite mean 30% less fat than the standard or original product, and more than 20g of fat per 100g makes a product high in fat.

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Which? executive director Richard Lloyd said: "Consumers are choosing low-fat and light options believing them to be a healthier choice, but our research has found that in many cases they're just not living up to their healthy image. Our advice to consumers is to read the nutritional labels carefully."

United Biscuits, which makes the McVitie's chocolate digestive, said the report was misleading. A spokesman said: "While it focused on the fact that the Lights variant of the McVitie's chocolate digestive had only eight fewer calories per biscuit than the standard product, it ignored the fact that the Lights version had 30% less fat.

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  • Realistic Goal

    A weight-loss goal should be challenging and require you to make an effort, but not be an impossible mission. Over ambitious targets can be easily broken! But by setting smaller goals, you have a real chance of reaching your wedding weight loss goal and boosting your confidence in your abilities to keep on track until you arrive at your destination. Aim to lose about five to ten per cent of your initial body weight over a 3-6 month period. Once you've reached your goal, treat yourself and your bridesmaids to celebrate your success and set another weight loss target.

  • Accept Setbacks

    Be prepared for the inevitable good and bad days. Don't get discouraged by the occasional set back. When days don't go according to plan, don't give up. As long as you are eating well most of the time, you can be less strict with yourself some of the time. Think positively, focus on your overall goals and get back on track -- tomorrow is a new (healthier) day. If you feel you are lacking motivation or hitting a slump, call on your bridesmaids or husband to be to help keep you on track.

  • Diary

    Keep a food and mood diary. Most of us literally don't know what we are eating, or how all the things we unconsciously eat are adding up - finishing of your child's fish fingers, testing wedding cake or nibbling on canapés during engagement celebrations! For long term weight loss you need to identify problem foods and 'areas of weaknesses' in your day. By keeping a food diary, you will become more aware of your eating patterns and the changes you need to make. Carry a small notebook with you and write down all the things you eat and drink on a typical day, along with any associated feelings. You can also keep your wedding to do list in here so everything is in one place. According to research in the American Journal of Preventative Medicine 'dieters' who jot down everything they eat and drink lose twice as much weight as those that don't.

  • Baby Steps

    There are lots of simple things you can do to kick start your wedding weight loss diet. You don't need to make big changes, just a few small steps can make a real difference to reaching your goal, whether it's looking at food labels to taking dance classes in preparation for your first dance, making sure you always start off the day with a healthy breakfast or signing yourself and your bridesmaids up to take part in a 5km charity race. As the Old Chinese Proverb said, it is better to take many small steps in the right direction than one great leap forward only to stumble backward.

  • Think Positively

    Focus on all the wonderful delicious, nutritious and seasonal foods that you can enjoy as part of your meals and for snacks, rather than all of the ones you need to cut back on. Eating is meant to be enjoyed and all foods have a place in a balanced diet. There is no such thing as good or bad foods, only good or bad eating habits -- save 'comfort foods' for an occasional treat with your fiancé or bridesmaids, not an everyday snack.

"Many consumers look to limit their fat intake and the Lights variant of McVitie's chocolate digestive helps them achieve this while still enjoying their favourite treat. Both the standard and light versions of McVitie's chocolate digestives clearly communicate the calories and other nutritional information per biscuit and per 100g. The calories per biscuit are also shown very clearly on front of pack in the GDA icon on both the Lights product and the standard product. This makes it clear for consumers to make a comparison if they choose to do so."

A Tesco spokeswoman said: "We take seriously our responsibility to help our customers make healthy choices. Our products display clear nutritional information on the front of the packaging and we always act in accordance with the strict rules around the use of words such as Reduced or Light."

See also:

Brits Underestimate Calories In Food, Warn Experts

Low-Calorie Food Trick The Body Into Gaining Weight