Bright Line Eating Diet Review

In this blog post I’m reviewing the Bright Line Eating diet from my lens as a dietitian.

A new diet is on the block called Bright Line Eating. It’s become pretty popular, even one of my best friends from college did it with her husband and they both had great success. The Bright Line Eating website is pretty vague on what the actual guidelines of the diet are, so I coughed up $13 to buy the book on this one to get all the deets.

Disclosures: None. This post wasn’t created in partnership with any product or brand.

Bright Line Eating Diet Review

I’ll start with a very short background of the author, give an overview of the diet, what I do and don’t like about it and whether or not I recommend it and why.

Meet the Bright Line Eating Author: Susan Peirce Thompson, PhD

In contrast to some other diet reviews I’ve done in the past, the author Dr. Susan Pierce Thompson actually has credentials. She does not have a background in nutrition, but did receive a PhD in Brain and Cognitive Sciences.

What is Bright Line Eating?

Bright Line Eating (BLE) is an extremely regimented diet program. The goal of BLE is for you to be “Happy, Thin and Free.” Following Bright Line Eating requires strict adherence to the four Bright Lines:

1. No sugar. Sugar naturally occurring in whole pieces of fruit is ok, although fruit in any other form (e.g. smoothies, juices) are a no.
2. No flour. This includes whole wheat flour and any grains or other substance ground into flour (i.e. no oats ground into flour, almond flour or the like).
3. 3 meals per day. Nothing between meals, virtually without exception.
4. Precise quantities. BLE has prescribed quantities which are to be measured using a digital food scale every meal, every day, ongoing.

Portion sizes and number of portions differ in the weight loss phase vs. the weight maintenance phase.

Weight Loss Phase

The weight loss phase looks like this:

• Breakfast includes a protein, a grain and a fruit.
• Lunch includes a protein, 6 oz vegetables, a fruit and a fat.
• Dinner includes a protein, 6 oz vegetables, 8 oz salad and a fat.

Men and women get slightly different protein portion sizes, which she outlines in her book but I will not here. There is no variance otherwise in the weight loss phase.

Notably, vegetable portions are not to use any fats in cooking (steaming is suggested, spray is allowed).

Maintenance Phase

The weight maintenance phase is harder to succinctly outline. After goal weight has been reached you add in additional servings until you stop losing weight. There are 16 additional serving steps, which I won’t outline in their entirety here (examples: add 4 oz cooked grain to lunch, increase breakfast grain to 1 1/2 servings, etc.). The first four steps are suggested for women. The first eight are suggested for men. Then there are extras for those who are still losing weight and need additional calories to maintain.

Importantly, after the new Bright Line portions are identified for weight maintenance, the Bright Liner is to continue measuring portions at meals as identified, indefinitely.

The Idea Behind Bright Line Eating

The author is a firm believer in food addiction, and particularly that sugar and flour are the addictive culprits. While there is currently no food addiction diagnosis per DSM-5 criteria, there is some emerging research on the topic (not necessarily specific to sugar and flour). Based upon Susan’s own experience in having food addiction, eating disorders bulimia nervosa and binge eating disorder, and her background in brain studies, her approach to quitting sugar, flour and measuring every meal to a T are like that of a smoker: you kick the habit and never look back.

Susan’s idea is that by following these Bright Lines it makes eating easy; you don’t have to decide what you will and won’t eat because you already decided. There is no room for moderation and there is no going back.

As a side, in my own experience helping treat eating disorders, I will say BLE certainly has a lot of strains of an eating disorder. I guess another way I could say that is, I’m not surprised the person who developed BLE has had serious disordered eating in the past.

Things I Like About Bright Line Eating

So let’s get into it nutritionally-speaking. Here’s what I like about Bright Line Eating, as a dietitian:

• It’s high in fiber.
• It’s high in protein.
• I agree most adults snack between meals for reasons other than hunger.
• It’s probably too few calories for a number of people, but it’s not crazy low in calories. For a woman in the weight loss phase, it clocks in at about just under 1400 calories-ish. Given Susan recommends individuals not exercise as they get their relationship with food under control, not every person is going to be in an alarmingly, net-negative calorie state.
• It actually is a fair amount of food, quantity-wise. Many would probably feel full from sheer volume given how many veggies are required, even though it will be lower in calories than most people have been eating prior to starting the program.
• There is adequate protein, carbohydrate and some fat (although it is a little low in fat, in my opinion).

Things I Don’t Like About Bright Line Eating

There are some positive points to BLE. There are, however, some things I don’t love about BLE:

• Lack of sustainability. There certainly are people who can stick with something this regimented, but it is just not reasonable for most people to weigh every food they eat for the rest of their lives. It’s not impossible to live life without added sugar or any type of flour, but to me it’s a little extreme.
• No accounting in portions for differences in body sizes. Given how precise BLE requires its portions to be, as someone who has calculated individual calorie needs for thousands of patients… you cannot blanket serving and ultimately calorie needs. Not every woman needs the same number of calories. Not every man needs the same number of calories. I get that she wrote a book and wants it to be translatable for everyone, but it’s too prescriptive without enough variability.
• Some of her nutrition information or suggestions are incorrect. For example, in BLE potatoes and sweet potatoes don’t count as starchy vegetables, they are counted as grains. But… potatoes are starchy veggies. In BLE, you’re allowed to have whole grains because they are high in fiber, but you’re not allowed to have any whole grains in flour form. But… whole grains, in flour form, are still high fiber. Similarly, Susan says fiber is lost in smoothies, which it is not (yes, it is lost in juicing). She says that hypoglycemia is caused by sugar and flour… which is just not correct. Lastly, we do not have evidence that sugar and flour are addictive. I’m not saying there isn’t emerging research on food addiction, but that’s a pointed statement to those specific food components.
• In my opinion, BLE is a bit disordered. Having worked in an inpatient eating disorder hospital unit, BLE has a lot of disordered traits. People with eating disorders love rules. They love control. They love following something. Precision is mastery in eating disorders. One of the hallmarks of eating disorders (particularly restrictive type) is lack of flexibility. The black and white, all or nothing nature of BLE just does not scream “recovery” or “positive relationship with food and my body” in the least. Not every person will have a negative response to following a diet so regimented, but guilt, shame and fears around food is not food freedom.

Bottom Line, Would You Recommend Bright Line Eating?

Let me lead with, I don’t necessarily think it’s unsafe, and a lot of people have found success with BLE. And for those who have had success and love it, I think that’s great. BUT – I personally would not recommend Bright Line Eating (I promise there are dietary patterns I do recommend!).

First, I think if you wanted to be that specific with your eating and portions to reach your health goals, you totally can but I would highly recommend working with a Registered Dietitian Nutritionist to calculate your personal needs if you intend to measure everything you eat. From there she can give you your number of servings of each food group if you wanted to go that direction, but I would not follow specific servings from a book that are intended for every male or female on the planet. And sure, if you wanted to cut sugar and flour out of the equation then you can, but I get hung up on the generalized-but-strict portions.

The second reason I would not recommend BLE is strictly just because I think there’s a high likelihood to instill disordered eating behaviors.

Lastly, I don’t think it’s sustainable for the majority of people. Personally, I prefer teaching long-term healthy eating principles and intuitive eating on portion sizing.

Have you heard of Bright Line Eating?

Have you tried Bright Line Eating?

What has your experience been with Bright Line Eating?