Sample size of one, and it may just be my biology, but over the last twenty years I have done this three times:
- Gain 50-70 lbs. over time, see skyrocketing blood pressure, and bad cholesterol, high fatigue, fuzzy thinking
- Get tired of it and cut all sugar and starch (i.e. no breads, sweets, soft drinks) out of my diet
- Lose 50-70 lbs. in the space of about 3 months, see blood pressure and cholesterol return to perfect, lose fatigue and fuzzy thinking problems
The first time I rationalized that it was more likely due to inadvertently reduced calorie count (after all, natural carbs are supposed to be good for you, and the foundation of your diet, while fats are supposed to be bad for you, and protein in moderation—that was the federal wisdom at the time). So I added sweet foods and starches back to my diet but kept to a lower calorie count. Within five years, I had put on tons of weight again.
The second time I sort of thought "worked once, probably will work again," so I cut out all sweeteners, natural or artificial, as well as all grains and grain flours. Three months down the line, I was skinny and healthy. "This time," I thought, "I'll adopt a lower calorie count when I return to a 'normal' diet." Well, another six or so years down the road, back up by 75+ pounds, even with calorie restriction and a conscious replacement of "refined" sugars with "natural" alternatives like honey and sticking to "whole grain, high fiber" starches and flours. I just plain got fat, even on the "natural" and "high fiber" stuff.
Third time cutting out sugars and starches just happened, started in about June of this year. Cut out all sweeteners and all grains. But consciously increased my caloric intake of protein and fat considerably as a kind of experiment. No limits. We're talking a full pound 70/30 beef patty sandwiched between two fried eggs for dinner territory. What many people at Whole Foods would call "heart-clogging food." Well... Dropped 75+ pounds in ~3 months. No calorie control at all, and not even thinking about moderating fat, protein, or salt intake. Same result, and again, blood pressure returned to excellent as did cholesterol, despite likely significantly higher cholesterol and salt intake. Energy levels are much higher. Alertness significantly improved.
Though some people worry about sustained ketosis as the result of diet, I have experienced no problems. This time, I'm not going back to a "normal diet." I feel like I have enough first-hand data for my own biology. I'm just gonna keep eating as much red meat, eggs, and butter as I want, along with low-sugar vegetables (esp. leafy greens like spinach and chard, etc.)
But sweet anything and grains are seriously off-limits.
I am still having trouble convincing relatives that this is a good idea, everyone is terribly worried about me. The fat will clog my arteries, the whole grains are good for me and I'll get colon cancer without them, etc. But I feel about 1,000% better without sugars and grains in my diet, and I can buy regular clothes as well.