They found less weight gain in people who ate more whole grains, fruits and non-starchy vegetables – like broccoli, carrots and spinach – and less refined grains, starchy vegetables and sweetened beverages.

Starchy vegetables are worse than sugar for weight maintenance?!

Starchy foods include white bread, peas, corn and potatoes, but also lentils and beans.

We can tell from other studies that starchy vegetables, especially legumes but also potatoes, do not cause weight gain, they even help with weight loss. (Aune D et al.))

An analysis of 21 studies found that people who ate legumes lost more weight on average than those who did not eat legumes (Vujicic I et al.)
Cooked potatoes do not appear to be a food that has an association with weight gain. Of the common foods, they have the highest effect on satiety.

Why do we see the opposite claim here? The catch is in the details.

In the study cited in the NBC article, they lumped sweet potatoes, boiled potatoes, baked potatoes, corn, peas, even French fries and potato chips into the group of starchy vegetables.

According to the U.S. Department of Agriculture’s (USDA) Economic Research Service, these are the most consumed starchy vegetable among American adults:

• Potatoes: 22.4 kilograms per person per year
• Tomatoes: 14.1 kilograms per person per year
• Corn: 11.1 kilograms per person per year

American adults often consume these foods in processed forms, such as French fries, pizza sauce, and cornbread. Processed starchy vegetables tend to be high in calories, sodium and unhealthy fats. French fries and potato chips encourage overeating.

Jordan Syatt lost 6kg in 30 days by eating sugar-rich foods

Trainer and fitness influencer Jordan Syatt has decided to eat foods that will raise his blood sugar for 30 days and lose weight at the same time. In doing so, he wanted to experimentally show that neither elevated insulin nor blood sugar hinder weight loss and thereby disprove the typical preconceptions associated with carbohydrates and especially sugars:

1. Insulin is the reason why we gain weight or prevents weight loss. This is why calories “don’t work”
2. Sweet foods cause hunger
3. Sugar is a poison / makes you unhealthy

“I’m making this video and taking it to the extreme to make a point that you can be spiking your blood sugar and lose weight.”

During the experiment, he consumed a variety of foods, including white bread, gummy candies, pumpkin lattes, potatoes, oatmeal, and even a quarter cup of pure refined sugar.

Here are his key observations:

• Fast carbohydrates (those with a high glycemic index) are said to cause a spike and subsequent drop in blood sugar. This causes fatigue and hunger. In some cases this is true, but not always. For example, after 4 slices of white bread, his sugar dropped 33 units without him experiencing hunger or a drop in energy. Similarly, after potatoes (80g carbs) his sugar went from 79 to 143! (Normally we don’t want to see an increase of more than 30 units). He felt great!
• After eating about 60g of pure sugar he felt super energetic at first, but after 2 hours there was a decline and for the next 2-3 hours he felt exhausted.
• The pumpkin spice latte (65g sugar) didn’t have much effect on his blood sugar. Probably due to the fact that it also contained fat and protein as opposed to pure sugar. It was basically like a meal replacement. He remarked, “It’s like I’m eating cheesecake in the form of a drink. I can’t even enjoy it, it’s too sweet. It’s great, but I don’t want to have it every day. I can’t believe people drink it every day. I’m not surprised they don’t want to eat fruit afterwards.”
• Healthy people nowadays pay a lot of attention to blood sugar and try to keep it in check. But judging foods only by how they affect blood sugar is not helpful. Oatmeal raised Jordan’s blood sugar more than gummy candy. That doesn’t mean gummy candies are healthier.
• You can lose weight even with high blood sugar. Jordan lost about 12 pounds (6kg)  in 30 days. But apart from the foods mentioned above, he also ate a varied, nutritious diet.
• His blood tests after the experiment showed an improvement in HDL cholesterol levels (probably due to weight loss), but his blood sugar and HbA1C levels were unchanged.

Sources:

1. Wan Y, Tobias D K, Dennis K K, Guasch-Ferré M, Sun Q, Rimm E B et al. Association between changes in carbohydrate intake and long term weight changes: prospective cohort study BMJ 2023; 382 :e073939 doi:10.1136/bmj-2022-073939
2. Vujicic I et al. The effects of legume consumption on body weight and body composition: A systematic review and meta-analysis of randomized controlled trials. Nutrients. 2016 Sep 14;8(9):569.
3. Aune D et al. Whole grain and legume consumption and changes in body weight and composition in the Iowa Women’s Health Study. Am J Clin Nutr. 2011 Oct;94(4):1165-71.
4. Potatoes and risk of chronic disease: a systematic review and dose–response meta-analysis https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6689281/
5. Potatoes and tomatoes are the most commonly consumed vegetables: USDA Economic Research Service, Food Availability and Consumption Data, available at https://www.ers.usda.gov/data-products/ag-and-food-statistic…
6. 50.3% of American adults consumed starchy vegetables on a given day: Centers for Disease Control and Prevention, Fruit and Vegetable Consumption Among Adults in the United States, 2015-2018, available at https://www.cdc.gov/nchs/products/databriefs/db397.htm
7. Chekima K, Yan SW, Lee SWen Huey, Wong TZe, Noor MI, Ooi YBH, Metzendorf M-I, Lai NM. Low glycaemic index or low glycaemic load diets for people with overweight or obesity. Cochrane Database of Systematic Reviews 2023, Issue 6. Art. No.: CD005105. DOI: 10.1002/14651858.CD005105.pub3. Accessed 22 October 2023.