Low fat? Low carb? Almost any healthy diet can work for losing weight

Howard LeWine, M.D.

Chief Medical Editor, Harvard Health Publishing

Yesterday’s nutrition headline was “low-carb, not low-fat, diet linked with increased weight loss.” Today it’s “no clear winner among popular diets.” The diet controversy continues.

For years, low-fat diets were the ones that doctors recommended for weight loss. Experts began to look closer at that advice when the low-carb Atkins and South Beach diets made huge splashes by helping some people lose weight.

Over the past 20 years, diets have been tested in head-to-head trials. Their results continue to illuminate nutrition advice and sometimes frustrate dieters. But there’s good news from this important research: almost any diet you stick with will work.

Latest results

Writing in yesterday’s Annals of Internal Medicine, a team of researchers reported the results of a randomized, controlled trial conducted at Tulane University Health Sciences Center in New Orleans. One hundred sixty eight overweight men and women without either heart disease or diabetes were randomly assigned to a low-carb diet (less than 40 grams of carbohydrates a day) or a low-fat diet (less than 30% of calories from fat). After 12 months, those on the low-carb diet had lost an average of 12 pounds, compared to 4 pounds in the low-fat group. The low-carb diet also had better effects on protective HDL cholesterol and other cardiovascular risk factors.

Today’s Journal of the American Medical Association tells a somewhat different story. A team of mostly Canadian researchers evaluated the results of 48 head-to-head trials of various named diets. These ranged from the low-carb Atkins and South Beach diets to moderates like Weight Watchers and Jenny Craig and low-fat approaches like the Ornish diet. After 12 months, average weight loss with either a low-carb or low-fat diet was the same, about 16 pounds. The researchers also found that the named diets yielded similar weight loss.

One thing that did make a difference was explicit advice to exercise more, or some sort of behavioral counseling along with advice on what to eat.

All healthy diets can be winners

The main message from careful comparisons of different diets is that there’s no single diet that’s right for everyone. Genes, family, environment, and many other factors determine how much each of us eats. Any healthy diet can help people lose weight. Some respond to one type better than another.

So if you are trying to lose weight, try one you think might work for you. If you give it your best shot and it doesn’t work, it’s possible that it isn’t right for you, your metabolism, taste buds, or situation. Try another.

Also keep in mind that there’s more to a diet than weight loss. You could put yourself on a hot dog diet and lose weight. But it wouldn’t be good for you in the long run. You need healthful nutrients day in and day out for overall good health. You also need an eating plan you can follow day in and day out that is good for your heart, bones, brain, and every other part of your body.

One eating strategy that can provide all that is the so-called Mediterranean diet. Many studies have linked following this type of diet to longer life and less heart disease, diabetes, cancer, and other chronic conditions.

There are many ways to “eat Mediterranean.” The basics include:

  • Four or more servings of vegetables a day. A serving is ½ cup of raw or cooked vegetables, 1 cup of raw leafy greens, or ½ cup of vegetable juice.
  • Four or more servings of fruit a day. A serving is ½ cup of fresh, frozen, or canned fruit; ¼ cup of dried fruit; one medium-sized piece of fruit; or ½ cup of fruit juice.
  • At least 4 tablespoons of olive oil a day.
  • One handful (about 1½ ounces) of nuts at least three times a week.
  • Three or more servings of beans, peas, lentils, or other legumes a week. A serving is ½ cup.
  • Six or more servings of whole grains a day. A serving is 1 cup of dry breakfast cereal; ½ cup of cooked cereal, brown rice, or whole-grain pasta; or one slice of whole-grain or multi-grain bread.
  • Three or more servings of fish (especially fatty fish) a week. A serving is 4 ounces.
  • One serving of yogurt or cheese a day.
  • If you enjoy alcohol, limit yourself to 1 (for women) or 2 (for men) drinks a day. One drink is 5 ounces of wine, 12 ounces of beer, or 1½ ounces of liquor.

At the same time, try not to drink sugar-sweetened soda, juice, or energy drinks. Have sweets, pastries, and commercial bakery goods only as the occasional treat. And go easy on red and processed meats.


  1. Daniel @Superchargedhuman.com

    This is an excellent article!

    Would I be able to reference this article on my website?



    • Kristen Rapoza

      Hi Dan,

      Yes, you can reference this article on your website as long as it is attributed to Harvard Health Publishing.

      Kristen @ Harvard Health Publishing

      • Colin

        Thanks Kristen,
        We’ll also like to post this excellent article on our website.
        We will make sure the have the proper attribution.
        I personally was very confused with the whole debate low-carb vs low-fat. 14 years ago I had a bypass surgery, and due my heart disease was advised to have a low fat diet. Which meant I was loading up on the carbs. Unfortunately over the years I’ve seen my blood sugars rise due to the carbs and the statins. Now I am taking a more balanced approach. So it’s helpful to get some good insights from a well written balanced article. Thanks

      • Kristen Rapoza

        You’re welcome Colin! I’m glad this article was helpful to you!

  2. deb

    Drink water eat lean meat eat green veggies have one cheat day a week and your fat belly will go away

  3. Kino

    Forget about diets. Just eat what we are supposed to eat. Vegetables! And drink what we are supposed to drink. Unchlorinated water!
    Avoid all dairy products. After weaning there is no need to be wet nursed, least of all by an animal.
    Avoid sugar! In my dictionary, The Australian Contemporary Dictionary, poison is defined as follows;

    Any substance which kills or injures when introduced into a living organism, that which has an evil influence on health…….Having a deadly or injurious quality…

    Refined sugar fits this description down to a tee. It has no benefit at all to humans, no food value, empty calories galore, it depletes the human system of vitamins and minerals, rots teeth, and is a causal factor in Osteoporosis, heart disease, sugar diabetes, obesity, glaucoma, and a hand full of other health problems.
    Following these guidelines will cause you to loose weight and generally feel better in all aspects of health

  4. Rainbow

    Excellent point made in the article. The desire to lose weight more importantly being healthy has to come from inside and any diet plan will work once determined to do so. Adding more of vegetables and fruits and being mindful of what we are eating is important. We need to think about eating as ‘eat to live not live to eat’


  5. healthyronments.com

    you say “try not to drink sugar-sweetened soda, juice, or energy drinks.” Why is it not recommended to consume juice? what if consume fruit juice without added sugar? sometimes consume dried fruit or fresh fruit will be something boring for some people.

  6. simmy singh

    In my point of view scientific data has proven that diet actually cause obesity. Besides the psychological, emotional & spiritual damage diets do the pattern of loosing & regaining weight can wreak havoc on your metabolism. Over time your body will try to stabilize your weight by automatically adjusting your metabolism & insulin production to attempt to maintain a set weight.

  7. George Morse

    Great points mentioned in this article. I would add the correlation between calorie restriction and successful weight loss.

  8. Anonymous

    In my opinion, low carb diets have shown better results through varying forms since the 1970s (ref Dr Atkins). In one form or another, these low carb diets still exist and the entycing element is that the dieter can still enjoy a lot of the food he/she currently enjoys. However, I agree that all have different advantages and as long as the dieter is disciplined, he/she will acheive the goal of losing weight.

  9. John Simon

    To reduce fat, it is not necessary to leave a big part of your daily diet.Just take daily diet including fruits, green vegetables, green leaves etc. and do a daily exercise. That’s sufficient, and definitely you will loose your belly.

  10. hari kumar

    Among all the artificial ways of reducing weight of the body, having a knowledge of foods which facilitate to decrease weight is the most valid. In that way the vegetables specified in this blog greatly helps the body.

  11. Psychologist gold coast

    It was most likely one of the things that we need learn for us to have a healthier life.low carbs is solid. In any case do you realize that there are additionally great carbs and awful carbs? Awful carbs comprise of those prepared sustenance like white bread, pasta, pop and baked goods.

  12. Kim Silverman

    It was definitely one of the things that we need learn for us to have a healthier life. Giving up carbs is hard, especially when we are used of eating those high carbs food. But do you know that there are also good carbs and bad carbs? Bad carbs consist of those processed food like white bread, pasta, soda and pastries. So we should avoid eating this kind of food. Good carbs are those complex carb grains like brown rice and oats. So it’s better to switch our diet to good carbs food.

  13. Kim Silverman

    It was definitely one of the things that we need learn for us to have a healthier life.Low carbs is healthy. But do you know that there are also good carbs and bad carbs? Bad carbs consist of those processed food like white bread, pasta, soda and pastries. So we should avoid eating this kind of food. Good carbs are those complex carb grains like brown rice and oats. So it’s better to switch our diet to good carbs food.

  14. hendrianto

    good! i will tray this diet

  15. Barry

    I just started my health eating plan after struggling with my weight for many years
    I have joined slimmers world and it seems to be working, I enjoyed reading this blog it has helped me understand more about low carbs as I find this topic confusing
    However I have found that getting rid of as much sugar out of my diet has the biggest impact on weight loss

    • John L

      My personal trainer at absolutefitnessnc always suggests a good diet plan plus time at the gym. I believe it’s called a health club for a reason. My trainer which is also the owner came up with a new method of working out called meta endurance training. If you have a hard time filling up on food try lean chicken or steak with seasonings. Good luck with your weight loss goals.

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