Low on Carbs, Low on Fats and LOW on Truth

Another research article hit the media this week, rewarding those who love to hear good news about their bad habits.

The Annals of Internal Medicine published a paper titled: “Effects of low-carb and low-fat diets.”  In it, the authors conclude, “the low carb diet was more effective for weight loss and cardiovascular risk factor reduction than the low fat diet. Restricting carbohydrate may be an option for persons seeking to lose weight and reduce cardiovascular risk.”

The media  – social and otherwise – celebrated: See? We always knew it. Those evil carbs. Fat is good. Pass on the grass-fed butter.

While I am waiting to read what Drs. Barnard, Greger and McDougall have to say about this paper, I will give you my interpretation of the data. It is very important that we understand what the message is here, since too much misleading and downright false information is being poured over the public.

Who is going to argue with the honorable Annals?  By the way: I should mention, that the authors did not receive any funds from industry. Their grant was from the NIH.

I am not going to write a detailed critique about the study methods; overall they are sound. Although the cohort is small, the participants were properly randomized to either the low fat or the low carb intervention group; this is a good epidemiological technique when designing an interventional study, where a question is being asked and the outcome is unknown. Here the question was: are low carb diets, which are so popular for weight loss, improving cardiovascular risk profiles or not?

For starters: let’s establish what a low carb diet is: the popular ones are Atkins, South Beach, Paleo and Zone, and several variations thereof.

As far as low-fat is concerned: the authors used the currently prevailing (and failing) definition propagated by the American Heart Association of 30% of fat calories from the daily calorie intake. There is a very large body of research evidence, that 30% fat does not constitute a healthy diet: All the studies done which showed reversal of coronary artery disease and type 2 diabetes allowed for 10-15% fat calories from total calorie intake. In other words: no diet containing 30% of fat prevented or reversed anything ever.

Participants assigned to the low-carbohydrate group were instructed to eat no more than 40g of carbs a day.

Participants assigned to the low-fat diet were instructed to eat no more than 30% of total calories from fat.

Participants were also instructed to have the “recommended dietary fiber intake of 25g/day.”

All participants were instructed in the different kinds of fats and educated about the need to avoid saturated and trans fats as much as possible, and to get as much monounsaturated fats as possible.

And that, folks, is ALL we know about the dietary content of the diets that the participants followed. Now, considering that the FOOD eaten was THE MOST IMPORTANT part of this study, don’t you think that it would have been ABSOLUTELY key to provide more detailed information about what the participants actually ate? Instead, the researchers are leaving this up to the readers’ imaginations. And that is a big problem: the main readers of this journal are physicians, and their imagination as far as nutrition goes is limited to non existent. As for the lay readers like “health journalists”: they read what they want to read. See above.

Where it gets really interesting in this paper, is on page 313: Table 2 titled “Daily dietary composition in the low-fat ad low-carbohydrate diet groups over the course of the study” gives an overview of the nutritional components of the diets.

Presumably the data listed on the left under “Baseline” represents the dietary values of the participants at the outset of the trial. Usually, this is done by having participants complete food frequency questionnaires, which are then evaluated by dietitians, and the appropriate calculations are made does this. The numbers in parenthesis (..) represent deviations from the average number. For example, in the low-fat group, the average calorie intake was 2034 calories a day, which could vary by about 702 calories either below or above (1332 – 2736 calories a day).

Once the two groups (low-fat and low-carb) received their instructions and education, their diets were analyzed again at 3, 6 and 12 months respectively. Again: most likely this was done by having people fill out questionnaires about their diets.

For starters: both groups had their calories cut by about 500 calories and this is really the definition of a weight loss caloric intake. But over time, caloric intake crept up in both groups, since cutting calories in general is not that easy.

Looking at the macronutrient make up (fat, protein and carbs) of the diets in both groups, the low-fat group consumed a diet consisting of 53% carbs, 19% protein and 27.5% fat.

The low-carb group consumed 29% carbs, 25.6% protein and 42.7 % fat on average. Hmm. What does that remind you of? Can you guess? Yep. Eco-Atkins, people.

“Instead of the steaks and bacon found in the original Atkins diet, dieters [in the study] were given prepared foods that consisted mostly of healthy fats, soy foods, beans, nuts, seeds, no-starch gluten products, fruits, and vegetables. Some 31% of the calories in the diet came from plant proteins, 43% from vegetable oils, and 26% from carbs.

Protein came primarily from gluten, soy beverages; tofu; soy burgers; veggie products such as bacon, breakfast links, and deli slices; nuts; vegetables; and cereals. The diet emphasized viscous vegetables like okra and eggplant, along with other low-starch vegetables.

The diet included “good fats” from canola oil, olive oil, avocado, and nuts. The dieters got carbs from fruits, vegetables, and cereals, with a limited amount of oats and barley. But they ate no starchy foods like enriched white bread, rice, potatoes, or baked goods.” http://www.atkins.com/Science/Articles—Library/Cardiovascular-Health/-The-“Eco-Atkins”-Diet.aspx

The excerpt taken from the Atkins website does not refer to the study I am critiquing here. But if you look at the macronutrient break down you HAVE to start laughing. Eco-Atkins has gone VEGAN!!!!

The above description of what the Eco-Atkins food plan consists of is all about plant based, minimally processed whole foods – with the exception of the veggie bacon and sausage, but we shall forgive them that one. No mention of dairy, meat, fish or eggs. Yippee!! Take that, Paleo people. The original Atkins camp must be crying.

What makes it “low-carb”? The omission of WHITE bread and BAKED GOODS, i.e. crackers, cookies, cakes, and other processed floury snacks. DUH!

The usual witch-hunt on rice and potatoes is laughable. BROWN – and even white – rice as well as potatoes that have not been drowned in oil and smothered in cheese are HEALTHY carbs, because their starches are complex and unrefined. PERIOD. But that’s for another blog.

And this, folks, is where the un-truths out there fester and multiply: when you throw CARBS into one big vat without differentiating, you commit nutritional crime.

All of us agree that PROCESSED carbs are the villains, whether you come from the Eco-Atkins, the Paleo or the WFPB (whole-foods, plant based) corner.

So, it would have been of immense value if the researchers had actually shared the ACTUAL food contents of the various diets eaten.

If the so called low-fat group (at 30% fat from calories) ate their 53% of carb calories from breads, cookies and baked goods, it’s no wonder that their triglycerides went up, their weight loss was less than stellar. Low-fat has gotten us over the years into great trouble: all those processed foods like cookies, cakes and snacks that are “low-fat” are nothing but gigantic processed carb traps, which contributed to making us fat and sick.

Let’s make it VERY clear: if indeed the so – called low carb group in the study ate a diet similar to Eco-Atkins, they were essentially instructed to eat a plant based, whole foods diet, which surely they had not eaten before, and thus, OF COURSE, they showed significant improvement in weight and several other parameters like blood pressure, plasma insulin and glucose levels as well as cholesterol, triglyceride and other lipid numbers. DUH again.

While their fat intake at about 43% is surely high, switching these people to plant fats instead of animal fats, and ELIMINATING cholesterol from their diets hat tremendously beneficial effects, despite the high overall fat content.

So, what is the conclusion from this study? Not what people who heard about it on TV want to hear:

  1. Eating high fat diets is still bad for you. But if you are going to replace all your animal based foods with plant-based foods, even a high(er) fat diet is still better for you than what you are eating right now. Nope, butter and dairy fat is still not health food. Nor are fish, chicken or beef.
  2. Getting your protein from plants instead of animals is what your body was designed for and what is going to reverse disease or prevent it altogether.
  3. As long as you are eating PLANT based, you are going to thrive, even if you play around with the percentages of protein, carbs and fats. In the “low-carb” category it means, that you are going to eat relatively small amounts of corn and peas, and lots and lots of greens and low carb veggies like tomatoes, cukes, carrots, peppers, broccoli, cauliflower etc. More power to YOU.
  4. What I absolutely don’t understand in this study: if people ate an eco-Atkins style diet in the low carb group, how on earth did they get so little fiber?

In conclusion: a low-fat PLANT based, minimally processed, whole foods diet will achieve all of the health benefits touted in the “low-carb” group and then some. It also happens to be the diet that provides the best protection from cancers, autoimmune diseases and many, many other chronic conditions – not to mention the BEST weight loss ever, which is also sustainable long term.

Reference:

Bazzano L.A. et al: Effects of low-carbohydrate and low-fat diets. A randomized trial. Ann Intern Med. 2014;161:309-318